Up through lcthw ex12

This reverts commit 52a5ea57e1.

.editorconfig

@@ -0,0 +1,11 @@
+root = true
+
+[*]
+end_of_line = lf
+insert_final_newline = true
+trim_trailing_whitespace = true
+max_line_length = 90
+
+[{*.c,*.go}]
+indent_style = tab
+indent_size = 4

lcthw/.envrc

@@ -0,0 +1 @@
+export CFLAGS='-Werror -g'

lcthw/.gdbinit

@@ -0,0 +1 @@
+set debuginfod enabled off

lcthw/.gitignore

@@ -0,0 +1,8 @@
+ex1
+ex3
+ex7
+ex8
+ex9
+ex10
+ex11
+ex12

lcthw/Makefile

@@ -0,0 +1,30 @@
+CFLAGS ?= -Wall -g
+GDBRUN = gdb --batch --ex run --ex bt --ex q --args
+BUILD_TARGETS = ex1 ex3 ex7 ex8 ex9 ex10 ex11 ex12
+TEST_TARGETS = ex1 ex3 ex7 ex8 ex9 ex11 ex12
+
+.PHONY: all
+all: build test
+
+.PHONY: clean
+clean:
+	rm -f $(BUILD_TARGETS)
+
+.PHONY: build
+build: $(BUILD_TARGETS)
+
+.PHONY: gtest
+gtest:
+	@$(foreach bt, \
+		$(TEST_TARGETS), \
+		printf '\n==> $(bt)\n' && $(GDBRUN) ./$(bt) && \
+	) \
+		printf '\ngYAY\n'
+
+.PHONY: test
+test:
+	@$(foreach bt, \
+		$(TEST_TARGETS), \
+		printf '\n==> %s\n' "$(bt)" && ./$(bt) && \
+	) \
+		printf '\nYAY\n'

lcthw/ex1.c

@@ -0,0 +1,12 @@
+#include <stdio.h>
+
+/* This is a comment. */
+int main(int argc, char *argv[])
+{
+	int distance = 100;
+
+	// this is also a comment
+	printf("You are %d miles away.\n", distance);
+
+	return 0;
+}

lcthw/ex10.c

@@ -0,0 +1,62 @@
+#include <stdio.h>
+
+int main(int argc, char *argv[])
+{
+	if (argc < 2) {
+		printf("ERROR: You need at least one argument.\n");
+		// this is how you abort a program
+		return 1;
+	}
+
+	int i = 0;
+	int arg = 1;
+	for (arg = 1; arg < argc; arg++) {
+		for (i = 0; argv[arg][i] != '\0'; i++) {
+			printf("(%d) ", arg);
+
+			char letter = argv[arg][i];
+
+			// lowercase letters
+			if (letter >= 'A' && letter <= 'Z') {
+				letter += ('a' - 'A');
+			}
+
+			switch (letter) {
+				case 'a':
+					printf("%d: 'a'\n", i);
+					break;
+
+				case 'e':
+					printf("%d: 'e'\n", i);
+					break;
+
+				case 'i':
+					printf("%d: 'i'\n", i);
+					break;
+
+				case 'o':
+					printf("%d: 'o'\n", i);
+					break;
+
+				case 'u':
+					printf("%d: 'u'\n", i);
+					break;
+
+				case 'y':
+					// why i > 2? is this a bug?
+					if (i > 2) {
+						// it's only sometimes Y
+						printf("%d: 'y'\n", i);
+					} else {
+						printf("%d: %c is not a vowel\n", i, letter);
+					}
+					break;
+
+				default:
+					printf("%d: %c is not a vowel\n", i, letter);
+			}
+		}
+	}
+
+	return 0;
+}

lcthw/ex11.c

@@ -0,0 +1,48 @@
+#include <stdio.h>
+
+int main(int argc, char *argv[])
+{
+	int numbers[4] = { 0 };
+	char name[4] = { 'a' };
+
+	// first, print them out raw
+	printf("numbers: %d %d %d %d\n",
+			numbers[0], numbers[1], numbers[2], numbers[3]);
+
+	printf("name each: %c %c %c %c\n",
+			name[0], name[1], name[2], name[3]);
+
+	printf("name: %s\n", name);
+
+	// setup the numbers
+	numbers[0] = 1;
+	numbers[1] = 2;
+	numbers[2] = 3;
+	numbers[3] = 4;
+
+	// setup the name
+	name[0] = 'Z';
+	name[1] = 'e';
+	name[2] = 'd';
+	name[3] = '\0';
+
+	// then print them out initialized
+	printf("numbers: %d %d %d %d\n",
+			numbers[0], numbers[1], numbers[2], numbers[3]);
+
+	printf("name each: %c %c %c %c\n",
+			name[0], name[1], name[2], name[3]);
+
+	// print the name like a string
+	printf("name: %s\n", name);
+
+	// another way to use name
+	char *another = "Zed";
+
+	printf("another: %s\n", another);
+
+	printf("another each: %c %c %c %c\n",
+			another[0], another[1], another[2], another[3]);
+
+	return 0;
+}

lcthw/ex12.c

@@ -0,0 +1,32 @@
+#include <stdio.h>
+
+int main(int argc, char *argv[])
+{
+	int areas[] = { 10, 12, 13, 14, 20 };
+	char name[] = "Zed";
+	char full_name[] = {
+		'Z', 'e', 'd',
+		' ', 'A', '.', ' ',
+		'S', 'h', 'a', 'w',
+	};
+
+	// WARNING: On some systems you may have to change the
+	// %ld in this code to a %u since it will use unsigned ints
+	printf("The size of an int: %ld\n", sizeof(int));
+	printf("The size of areas (int[]): %ld\n", sizeof(areas));
+	printf("The number of ints in areas: %ld\n",
+			sizeof(areas) / sizeof(int));
+	printf("The first area is %d, the 2nd %d.\n", areas[0], areas[1]);
+
+	printf("The size of a char: %ld\n", sizeof(char));
+	printf("The size of name (char[]): %ld\n", sizeof(name));
+	printf("The number of chars: %ld\n", sizeof(name) / sizeof(char));
+
+	printf("The size of full_name (char[]): %ld\n", sizeof(full_name));
+	printf("The number of chars: %ld\n",
+			sizeof(full_name) / sizeof(char));
+
+	printf("name=\"%s\" and full_name=\"%s\"\n", name, full_name);
+
+	return 0;
+}

lcthw/ex3.c

@@ -0,0 +1,12 @@
+#include <stdio.h>
+
+int main(int argc, char *argv[])
+{
+	int age = 10;
+	int height = 72;
+
+	printf("I am %d years old.\n", age);
+	printf("I am %d inches tall.\n", height);
+
+	return 0;
+}

lcthw/ex7.c

@@ -0,0 +1,43 @@
+#include <stdio.h>
+
+int main(int argc, char* argv[])
+{
+	int distance = 100;
+	float power = 2.345f;
+	double super_power = 56789.4532;
+	char initial = 'A';
+	char first_name[] = "Zed";
+	char last_name[] = "Shaw";
+
+	printf("You are %d miles away.\n", distance);
+	printf("You have %f levels of power.\n", power);
+	printf("You have %f awesome super powers.\n", super_power);
+	printf("I have an initial %c.\n", initial);
+	printf("I have a first name %s.\n", first_name);
+	printf("I have a last name %s.\n", last_name);
+	printf("My whole name is %s %c. %s.\n",
+			first_name, initial, last_name);
+
+	int bugs = 100;
+	double bug_rate = 1.2;
+
+	printf("You have %d bugs at the imaginary rate of %f.\n",
+			bugs, bug_rate);
+
+	long universe_of_defects = 1L * 1024L * 1024L * 1024L;
+	printf("The entire universe has %ld bugs.\n", universe_of_defects);
+
+	double expected_bugs = bugs * bug_rate;
+	printf("You are expected to have %f bugs.\n", expected_bugs);
+
+	double part_of_universe = expected_bugs / universe_of_defects;
+	printf("That is only a %e portion of the universe.\n",
+			part_of_universe);
+
+	// this makes no sense, just a demo of something weird
+	char nul_byte = '\0';
+	int care_percentage = bugs * nul_byte;
+	printf("Which means you should care %d%%.\n", care_percentage);
+
+	return 0;
+}

lcthw/ex8.c

@@ -0,0 +1,21 @@
+#include <stdio.h>
+
+int main(int argc, char* argv[])
+{
+	int i = 0;
+
+	if (argc == 1) {
+		printf("You have no argument.\n");
+	} else if (argc > 1 && argc < 4) {
+		printf("Here's your arguments:\n");
+
+		for (i = 0; i < argc; i++) {
+			printf("%s ", argv[i]);
+		}
+		printf("\n");
+	} else {
+		printf("You have too many arguments.\n");
+	}
+
+	return 0;
+}

lcthw/ex9.c

@@ -0,0 +1,15 @@
+#include <stdio.h>
+
+int main(int argc, char *argv[])
+{
+	int i = 25;
+	while (i > 0) {
+		printf("%d", i);
+		i--;
+	}
+
+	// need this to add a final newline
+	printf("\n");
+
+	return 0;
+}

leetcode/.gitignore

@@ -0,0 +1 @@
+.envrc

leetcode/.python-version

@@ -0,0 +1 @@
+3.12.0

leetcode/pyproject.toml

@@ -0,0 +1,147 @@
+[build-system]
+requires = ["hatchling"]
+build-backend = "hatchling.build"
+
+[project]
+name = "leetcode"
+description = 'What A Mess'
+readme = "README.md"
+version = "0.1.0"
+requires-python = ">=3.7"
+license = "MIT"
+keywords = []
+authors = [
+  { name = "Dan Buch", email = "dan@meatballhat.com" },
+]
+classifiers = []
+dependencies = [
+  "ipython",
+  "ipdb",
+  "matplotlib",
+  "numpy"
+]
+
+[tool.hatch.envs.default]
+dependencies = [
+  "coverage[toml]>=6.5",
+  "pytest",
+]
+[tool.hatch.envs.default.scripts]
+test = "pytest {args:tests}"
+test-cov = "coverage run -m pytest {args:tests}"
+cov-report = [
+  "- coverage combine",
+  "coverage report",
+]
+cov = [
+  "test-cov",
+  "cov-report",
+]
+
+[[tool.hatch.envs.all.matrix]]
+python = ["3.7", "3.8", "3.9", "3.10", "3.11"]
+
+[tool.hatch.envs.lint]
+detached = true
+dependencies = [
+  "black>=23.1.0",
+  "mypy>=1.0.0",
+  "ruff>=0.0.243",
+]
+[tool.hatch.envs.lint.scripts]
+typing = "mypy --install-types --non-interactive {args:.}"
+style = [
+  "ruff {args:.}",
+  "black --check --diff {args:.}",
+]
+fmt = [
+  "black {args:.}",
+  "ruff --fix {args:.}",
+  "style",
+]
+all = [
+  "style",
+  "typing",
+]
+
+[tool.black]
+target-version = ["py37"]
+line-length = 90
+
+[tool.ruff]
+target-version = "py37"
+line-length = 90
+select = [
+  "A",
+  "ARG",
+  "B",
+  "C",
+  "DTZ",
+  "E",
+  "EM",
+  "F",
+  "FBT",
+  "I",
+  "ICN",
+  "ISC",
+  "N",
+  "PLC",
+  "PLE",
+  "PLR",
+  "PLW",
+  "Q",
+  "RUF",
+  "S",
+  "T",
+  "TID",
+  "UP",
+  "W",
+  "YTT",
+]
+ignore = [
+  # Allow non-abstract empty methods in abstract base classes
+  "B027",
+  # Allow boolean positional values in function calls, like `dict.get(... True)`
+  "FBT003",
+  # Ignore checks for possible passwords
+  "S105", "S106", "S107",
+  # Ignore complexity
+  "C901", "PLR0911", "PLR0912", "PLR0913", "PLR0915",
+  # Allow print func
+  "T201",
+  # Allow assert statements
+  "S101",
+]
+unfixable = [
+  # Don't touch unused imports
+  "F401",
+]
+
+[tool.ruff.isort]
+known-first-party = ["leetcode"]
+
+[tool.ruff.flake8-tidy-imports]
+ban-relative-imports = "all"
+
+[tool.ruff.per-file-ignores]
+# Tests can use magic values, assertions, and relative imports
+"tests/**/*" = ["PLR2004", "S101", "TID252"]
+
+[tool.coverage.run]
+source_pkgs = ["leetcode", "tests"]
+branch = true
+parallel = true
+omit = [
+  "src/leetcode/__about__.py",
+]
+
+[tool.coverage.paths]
+leetcode = ["src/leetcode", "*/leetcode/src/leetcode"]
+tests = ["tests", "*/leetcode/tests"]
+
+[tool.coverage.report]
+exclude_lines = [
+  "no cov",
+  "if __name__ == .__main__.:",
+  "if TYPE_CHECKING:",
+]

leetcode/roman.py

@@ -0,0 +1,57 @@
+SIMPLE = {
+    "I": 1,
+    "V": 5,
+    "X": 10,
+    "L": 50,
+    "C": 100,
+    "D": 500,
+    "M": 1000,
+}
+SIMPLE_REVERSE = {v: k for k, v in SIMPLE.items()}
+COMPOUND = {
+    "IV": 4,
+    "IX": 9,
+    "XL": 40,
+    "XC": 90,
+    "CD": 400,
+    "CM": 900,
+}
+PREFIXES = {k[0] for k in COMPOUND.keys()}
+COMPOUND_REVERSE = {v: k for k, v in COMPOUND.items()}
+ALL = SIMPLE | COMPOUND
+ALL_REVERSE = {v: k for k, v in ALL.items()}
+
+
+def i2r(i: int) -> str:
+    if i > 100_000:
+        raise ValueError(f"{i} is too silly")
+
+    r: list[str] = []
+
+    for int_val, roman_val in sorted(ALL_REVERSE.items(), reverse=True):
+        remainder = i % int_val
+
+        r += [roman_val] * int((i - remainder) / int_val)
+
+        i = remainder
+
+    return "".join(r)
+
+
+def r2i(r: str) -> int:
+    total = 0
+    offset = 0
+
+    for i in range(len(r)):
+        if i + offset > len(r) - 1:
+            break
+
+        c = r[i + offset]
+        if c in PREFIXES and (i + offset + 1) < len(r) and c + r[i + offset + 1] in ALL:
+            total += ALL[c + r[i + offset + 1]]
+            offset += 1
+            continue
+
+        total += ALL[c]
+
+    return total

leetcode/spiral_matrix.py

@@ -0,0 +1,57 @@
+import itertools
+import typing
+
+
+def matrix_spiral(matrix: list[list[typing.Any]]) -> list[typing.Any]:
+    return [matrix[y][x] for x, y in matrix_spiral_path(matrix)]
+
+
+def matrix_spiral_path(matrix: list[list[int]]) -> list[tuple[int, int]]:
+    snek = SpinSnek(matrix)
+
+    while snek.step():
+        ...
+
+    return snek.path
+
+
+COMPASS = (
+    (1, 0),  # east
+    (0, 1),  # south
+    (-1, 0),  # west
+    (0, -1),  # north
+)
+
+
+class SpinSnek:
+    def __init__(self, board: list[list[int]], loc: tuple[int, int] = (0, 0)):
+        self.max_loc: tuple[int, int] = (len(board[0]) - 1, len(board) - 1)
+        self.spinner: itertools.cycle[tuple[int, int]] = itertools.cycle(COMPASS)
+        self.direction = next(self.spinner)
+        self.path: list[tuple[int, int]] = [loc]
+        self.missteps: int = 0
+
+    def step(self) -> bool:
+        loc = self.path[-1]
+        next_loc: tuple[int, int] = (
+            loc[0] + self.direction[0],
+            loc[1] + self.direction[1],
+        )
+
+        if (
+            next_loc[0] > self.max_loc[0]
+            or next_loc[1] > self.max_loc[1]
+            or next_loc[0] < 0
+            or next_loc[1] < 0
+            or next_loc in self.path
+        ):
+            self.direction = next(self.spinner)
+            if self.missteps > len(COMPASS) - 1:
+                return False
+
+            self.missteps += 1
+            return self.step()
+
+        self.missteps: int = 0
+        self.path.append(next_loc)
+        return True

leetcode/stdlib.py

@@ -0,0 +1,169 @@
+import dataclasses
+import typing
+
+
+class LinkedListNode(typing.Protocol):
+    val: int
+    next: typing.Optional["LinkedListNode"]
+
+
+class ListNode:
+    """ListNode is the leetcode "standard library" type used in linked lists"""
+
+    def __init__(self, val: int = 0, next: typing.Optional["ListNode"] = None):  # no qa
+        self.val = val
+        self.next = next
+
+
+class ListNodeRandom:
+    """ListNodeRandom is another weirdo linked list thing from
+    leetcode that is obviously very different than a binary tree
+    node :upside_down_face:
+    """
+
+    def __init__(
+        self,
+        x: int,
+        next: typing.Optional["ListNodeRandom"] = None,
+        random: typing.Optional["ListNodeRandom"] = None,
+    ):
+        self.val = x
+        self.next = next
+        self.random = random
+
+
+@dataclasses.dataclass
+class ListNodeRandomNicely:
+    val: int
+    next: typing.Optional["ListNodeRandomNicely"] = None
+    random: typing.Optional["ListNodeRandomNicely"] = None
+
+
+class BinaryTreeNode(typing.Protocol):
+    val: int
+    left: typing.Optional["BinaryTreeNode"]
+    right: typing.Optional["BinaryTreeNode"]
+
+
+class TreeNode:
+    """TreeNode is the leetcode "standard library" type used in binary trees"""
+
+    def __init__(
+        self,
+        val: int = 0,
+        left: typing.Optional["TreeNode"] = None,
+        right: typing.Optional["TreeNode"] = None,
+    ):
+        self.val = val
+        self.left = left
+        self.right = right
+
+    @classmethod
+    def from_int(cls, val: int | None) -> typing.Optional["TreeNode"]:
+        if val is None:
+            return None
+
+        return TreeNode(val)
+
+    # __repr__ was added by me
+    def __repr__(self) -> str:
+        filtered_parts = []
+
+        for key, value in [
+            ("val", self.val),
+            ("left", self.left),
+            ("right", self.right),
+        ]:
+            if value is not None:
+                filtered_parts.append((key, value))
+
+        middle = ", ".join([f"{k}={v!r}" for k, v in filtered_parts])
+
+        return f"TreeNode({middle})"
+
+    # __eq__ was added by me
+    def __eq__(self, other: typing.Optional["TreeNode"]) -> bool:
+        return (
+            other is not None
+            and self.val == other.val
+            and self.left == other.left
+            and self.right == other.right
+        )
+
+
+class ConnectableBinaryTreeNode(typing.Protocol):
+    val: int
+    left: typing.Optional["BinaryTreeNode"]
+    right: typing.Optional["BinaryTreeNode"]
+    next: typing.Optional["BinaryTreeNode"]
+
+
+class Node:
+    """Node is the *other* leetcode "standard library" type used in binary trees"""
+
+    def __init__(
+        self,
+        val: int = 0,
+        left: typing.Optional["Node"] = None,
+        right: typing.Optional["Node"] = None,
+        next: typing.Optional["Node"] = None,  # no qa
+    ):
+        self.val = val
+        self.left = left
+        self.right = right
+        self.next = next
+
+    # __repr__ was added by me
+    def __repr__(self) -> str:
+        filtered_parts = []
+
+        for key, value in [
+            ("val", self.val),
+            ("right", self.right),
+            ("left", self.left),
+            ("next", self.next),
+        ]:
+            if value is not None:
+                filtered_parts.append((key, value))
+
+        middle = ", ".join([f"{k}={v!r}" for k, v in filtered_parts])
+
+        return f"Node({middle})"
+
+    # __eq__ was added by me
+    def __eq__(self, other: "Node") -> bool:
+        return (
+            other is not None
+            and self.val == other.val
+            and self.left == other.left
+            and self.right == other.right
+            and self.next == other.next
+        )
+
+    # __list__ was added by me
+    def __list__(self) -> list[int | None]:
+        ret = [self.val]
+        ret += self.right.__list__() if self.right is not None else [None]
+        ret += self.left.__list__() if self.left is not None else [None]
+        ret += self.next.__list__() if self.next is not None else [None]
+        return ret
+
+
+class NeighborlyNode:
+    """NeighborlyNode is a "Node" type used in leetcode graph puzzles"""
+
+    def __init__(self, val=0, neighbors=None):
+        self.val = val
+        self.neighbors = neighbors if neighbors is not None else []
+
+
+class NeighborlyNodeNicely(typing.NamedTuple):
+    val: int
+    neighbors: list["NeighborlyNodeNicely"]
+
+    def __eq__(self, other: typing.Optional["NeighborlyNodeNicely"]) -> bool:
+        return (
+            other is not None
+            and self.val == other.val
+            and [n.val for n in self.neighbors] == [n.val for n in other.neighbors]
+        )

leetcode/stuff.py

@@ -0,0 +1,640 @@
+import collections.abc
+import copy
+import random
+import typing
+
+import stdlib
+
+
+def yep(s: str) -> bool:
+    return s.strip().lower().startswith("y")
+
+
+def guess_bisect_repl(lower: int, upper: int) -> int:
+    mid = lower + ((upper - lower) // 2)
+
+    if yep(input(f"is it {mid}? ")):
+        return mid
+
+    if yep(input(f"higher than {mid}? ")):
+        return guess_bisect_repl(mid, upper)
+
+    return guess_bisect_repl(lower, mid)
+
+
+def find_sqrt_ish(n: int) -> int:
+    return int(find_bisect(0, n, gen_sqrt_check(n)))
+
+
+def gen_sqrt_check(n: int) -> typing.Callable[[float], int]:
+    def check(mid: float) -> int:
+        mid_sq: float = mid * mid
+
+        if mid_sq == n:
+            return 0
+
+        if mid_sq < n:
+            return 1
+
+        return -1
+
+    return check
+
+
+def find_bisect(
+    lower: float, upper: float, check: typing.Callable[[float], int]
+) -> float:
+    mid: float = lower + ((upper - lower) / 2)
+
+    print(f"lower={lower} mid={mid} upper={upper}")
+
+    if mid == lower or mid == upper or check(mid) == 0:
+        return mid
+
+    if check(mid) == 1:
+        return find_bisect(mid, upper, check)
+
+    return find_bisect(lower, mid, check)
+
+
+def cartesian_path(p0: tuple[int, int], p1: tuple[int, int]) -> list[tuple[int, int]]:
+    path: list[tuple[int, int]] = []
+
+    if p0 < p1:
+        for i in range(p0[1], p1[1]):
+            path.append((i, p0[0]))
+
+        for i in range(p0[0], p1[0]):
+            path.append((p1[1], i))
+
+    else:
+        for i in range(p0[1], p1[1] - 1, -1):
+            path.append((i, p0[0]))
+
+        for i in range(p0[0] - 1, p1[0], -1):
+            path.append((p1[1], i))
+
+    return path
+
+
+def gen_matrix(width: int, height: int) -> list[list[int]]:
+    return [list(range(width)) for _ in range(height)]
+
+
+class MinStack:
+    def __init__(self):
+        self._v: list[int] = []
+        self._min: list[int] = []
+
+    def push(self, val: int) -> None:
+        self._v.append(val)
+        self._min.append(min(val, self._min[-1] if self._min else val))
+
+    def pop(self) -> None:
+        self._v.pop(-1)
+        self._min.pop(-1)
+
+    def top(self) -> int:
+        return self._v[-1]
+
+    def getMin(self) -> int:  # no qa
+        return self._min[-1]
+
+
+def linked_list_to_list(head: stdlib.LinkedListNode | None) -> list[int]:
+    seen: set[int] = set()
+    ret: list[int] = []
+
+    while head is not None:
+        if hash(head) in seen:
+            return ret
+
+        seen.add(hash(head))
+        ret.append(head.val)
+        head = head.next
+
+    return ret
+
+
+def sort_linked_list(head: stdlib.LinkedListNode | None) -> stdlib.LinkedListNode | None:
+    by_val: list[tuple[int, stdlib.LinkedListNode]] = []
+    ret: stdlib.LinkedListNode | None = None
+
+    while head is not None:
+        by_val.append((head.val, head))
+        head = head.next
+
+    cur = ret
+
+    for _, node in sorted(by_val, key=lambda v: v[0]):
+        if cur is None:
+            cur = ret = node
+            continue
+
+        cur.next = node
+        cur = cur.next
+
+    if cur is not None:
+        cur.next = None
+
+    return ret
+
+
+def connect_binary_tree_right(
+    root: stdlib.ConnectableBinaryTreeNode | None,
+) -> tuple[stdlib.ConnectableBinaryTreeNode | None, list[int | None]]:
+    if root is None:
+        return None, []
+
+    by_level = binary_tree_by_level(copy.deepcopy(root))
+    by_level = typing.cast(dict[int, list[stdlib.ConnectableBinaryTreeNode]], by_level)
+    serialized: list[int | None] = []
+
+    print("")
+
+    if 0 not in by_level or len(by_level[0]) == 0:
+        return None, []
+
+    connected_root = by_level[0][0]
+
+    for level, nodes in sorted(by_level.items(), key=lambda p: p[0]):
+        for i in range(len(nodes)):
+            serialized.append(nodes[i].val)
+
+            if len(nodes) > i + 1:
+                print(f"{'-' * level}> connecting {nodes[i].val} -> {nodes[i + 1].val}")
+                nodes[i].next = nodes[i + 1]
+
+        serialized.append(None)
+
+    return connected_root, serialized
+
+
+def binary_tree_by_level(
+    root: stdlib.BinaryTreeNode,
+) -> dict[int, list[stdlib.BinaryTreeNode]]:
+    combined: dict[int, list[stdlib.BinaryTreeNode]] = {}
+
+    for path in collect_binary_tree_levels(0, root):
+        level, node = path
+        combined.setdefault(level, [])
+        combined[level].insert(0, node)
+
+    return combined
+
+
+def collect_binary_tree_levels(
+    level: int, node: stdlib.BinaryTreeNode | None
+) -> typing.Iterator[tuple[int, stdlib.BinaryTreeNode]]:
+    if node is None:
+        return
+
+    yield (level, node)
+    yield from collect_binary_tree_levels(level + 1, node.right)
+    yield from collect_binary_tree_levels(level + 1, node.left)
+
+
+def sum_binary_tree_path_ints(root: stdlib.BinaryTreeNode | None) -> int:
+    path_ints: list[int] = []
+
+    for path in collect_binary_tree_paths(root):
+        path_ints.append(int("".join([str(node.val) for node in path])))
+
+    return sum(path_ints)
+
+
+def binary_tree_paths_as_lists(
+    paths: list[list[stdlib.BinaryTreeNode]],
+) -> list[list[int]]:
+    paths_vals: list[list[int]] = []
+
+    for path in paths:
+        paths_vals.append([node.val for node in path])
+
+    return paths_vals
+
+
+def collect_binary_tree_paths(
+    node: stdlib.BinaryTreeNode | None,
+) -> typing.Iterator[list[stdlib.BinaryTreeNode]]:
+    if node is None:
+        return
+
+    if node.right is None and node.left is None:
+        yield [node]
+        return
+
+    if node.right is not None:
+        for path in collect_binary_tree_paths(node.right):
+            yield [node] + path
+
+    if node.left is not None:
+        for path in collect_binary_tree_paths(node.left):
+            yield [node] + path
+
+
+def binary_tree_from_list(inlist: list[int | None]) -> stdlib.BinaryTreeNode | None:
+    if len(inlist) == 0:
+        return None
+
+    nodes: list[stdlib.BinaryTreeNode | None] = [
+        typing.cast(stdlib.BinaryTreeNode | None, stdlib.TreeNode.from_int(i))
+        for i in inlist
+    ]
+    nodes_copy = nodes[::-1]
+    root = nodes_copy.pop()
+
+    for node in nodes:
+        if node is None:
+            continue
+
+        if len(nodes_copy) == 0:
+            break
+
+        node.left = nodes_copy.pop()
+
+        if len(nodes_copy) > 0:
+            node.right = nodes_copy.pop()
+
+    return root
+
+
+def binary_tree_from_preorder_inorder(
+    preorder: list[int], inorder: list[int]
+) -> stdlib.BinaryTreeNode | None:
+    preorder_reversed = preorder[::-1]
+
+    def subtree(left: list[int], right: list[int]) -> stdlib.BinaryTreeNode:
+        root: stdlib.BinaryTreeNode = typing.cast(
+            stdlib.BinaryTreeNode, stdlib.TreeNode(preorder_reversed.pop())
+        )
+
+        if len(left) > 1:
+            split_pos = left.index(preorder_reversed[-1])
+            root.left = subtree(left[:split_pos], left[split_pos + 1 :])
+        elif len(left) == 1:
+            preorder_reversed.remove(left[0])
+            root.left = typing.cast(stdlib.BinaryTreeNode, stdlib.TreeNode(left[0]))
+
+        if len(right) > 1:
+            split_pos = right.index(preorder_reversed[-1])
+            root.right = subtree(right[:split_pos], right[split_pos + 1 :])
+        elif len(right) == 1:
+            preorder_reversed.remove(right[0])
+            root.right = typing.cast(stdlib.BinaryTreeNode, stdlib.TreeNode(right[0]))
+
+        return root
+
+    split_pos = inorder.index(preorder[0])
+
+    return subtree(inorder[:split_pos], inorder[split_pos + 1 :])
+
+
+class JumpSpace(typing.NamedTuple):
+    pos: int
+    val: int
+    moves: list["JumpSpace"]
+
+    @classmethod
+    def from_board(
+        cls, pos: int = 0, board: typing.Iterable[int] = ()
+    ) -> typing.Optional["JumpSpace"]:
+        board = list(board)
+
+        if len(board) == 0:
+            return None
+
+        space = cls(pos, board[pos], [])
+        space.collect(board)
+        return space
+
+    def collect(self, board: list[int]) -> None:
+        del self.moves[:]
+
+        if self.pos > len(board) or len(board) == 0:
+            return
+
+        for n in range(self.pos + 1, self.pos + self.val + 1):
+            if n >= len(board):
+                break
+
+            self.moves.append(typing.cast(JumpSpace, JumpSpace.from_board(n, board)))
+
+    def jump_paths(self) -> list[list[int]]:
+        ret: list[list[int]] = [[self.pos]]
+
+        for next_space in self.moves:
+            for path in next_space.jump_paths():
+                ret.append([self.pos] + path)
+
+        return ret
+
+
+def collect_complete_jump_paths_from_board(board: list[int]) -> list[list[int]]:
+    return [
+        p
+        for p in collect_jump_paths_from_board(board)
+        if len(p) > 0 and p[-1] >= len(board) - 1
+    ]
+
+
+def collect_jump_paths_from_board(board: list[int]) -> list[list[int]]:
+    space = JumpSpace.from_board(0, board)
+    if space is None:
+        return []
+
+    return space.jump_paths()
+
+
+# NOTE: the expensive way goes like this
+# complete_paths = collect_complete_jump_paths_from_board(board)
+
+# if len(complete_paths) == 0:
+#     return -1
+
+# return min([len(p) - 1 for p in complete_paths])
+
+
+def count_min_jumps_from_board(board: list[int]) -> int:
+    return len(collect_min_jumps_from_board(board))
+
+
+def collect_min_jumps_from_board(board: list[int]) -> list[int]:
+    if len(board) < 3:
+        return list(range(1, len(board)))
+
+    jumps: list[int] = []
+    range_begin: int = 0
+    val = board[range_begin]
+    range_end: int = range_begin + val + 1
+
+    while range_end < len(board):
+        potential_jumps = board[range_begin:range_end]
+
+        scored_jumps = [
+            (val + range_begin + i, val, range_begin + i)
+            for i, val in enumerate(potential_jumps)
+        ]
+        _, val, space = max(scored_jumps)
+
+        jumps.append(space)
+
+        range_begin = space
+        range_end = range_begin + val + 1
+
+    return jumps + [len(board) - 1]
+
+
+def h_index(citations: list[int]) -> int:
+    last_qualified = None
+
+    for i, citation_count in enumerate(list(sorted(citations, reverse=True))):
+        if citation_count >= i + 1:
+            last_qualified = i + 1
+        else:
+            break
+
+    return last_qualified or 0
+
+
+class SlowRandomizedSet:
+    def __init__(self):
+        self._i: set[int] = set()
+
+    def insert(self, val: int) -> bool:
+        ok = val not in self._i
+        self._i.add(val)
+        return ok
+
+    def remove(self, val: int) -> bool:
+        if val in self._i:
+            self._i.remove(val)
+            return True
+        return False
+
+    def getRandom(self) -> int:
+        return random.choice(list(self._i))
+
+
+class RandomizedSet:
+    def __init__(self):
+        self._l: list[int] = []
+        self._m: dict[int, int] = {}
+
+    def insert(self, val: int) -> bool:
+        if val in self._m:
+            return False
+
+        self._m[val] = len(self._l)
+        self._l.append(val)
+
+        return True
+
+    def remove(self, val: int) -> bool:
+        if val not in self._m:
+            return False
+
+        val_loc = self._m[val]
+        last_val = self._l[-1]
+        self._l[val_loc] = last_val
+        self._m[last_val] = val_loc
+
+        self._l.pop()
+        self._m.pop(val)
+
+        return True
+
+    def getRandom(self) -> int:
+        return random.choice(self._l)
+
+
+class TrieNode(typing.NamedTuple):
+    value: str
+    kids: dict[str, "TrieNode"]
+
+    @property
+    def is_leaf(self) -> bool:
+        return "__self__" in self.kids
+
+    @classmethod
+    def leaf(cls) -> "TrieNode":
+        return cls("__self__", {})
+
+
+class Trie:
+    def __init__(self):
+        self._root_node = TrieNode("", {})
+
+    def insert(self, word: str) -> None:
+        if len(word) == 0:
+            return
+
+        current_node = self._root_node
+
+        for prefix in [word[: i + 1] for i in range(len(word))]:
+            current_node.kids.setdefault(prefix, TrieNode(prefix, {}))
+            current_node = current_node.kids[prefix]
+
+        leaf = TrieNode.leaf()
+        current_node.kids[leaf.value] = leaf
+
+    def search(self, word: str) -> bool:
+        return self._has(word, prefix_ok=False)
+
+    def startsWith(self, prefix: str) -> bool:
+        return self._has(prefix, prefix_ok=True)
+
+    def _has(self, word: str, prefix_ok: bool) -> bool:
+        if len(word) == 0:
+            return True
+
+        reverse_path = [word[: i + 1] for i in range(len(word))][::-1]
+        current_node = self._root_node
+
+        while reverse_path and current_node is not None:
+            current_node = current_node.kids.get(reverse_path.pop())
+
+        return (
+            current_node is not None
+            and (current_node.is_leaf or prefix_ok)
+            and current_node.value == word
+        )
+
+
+def count_factorial_trailing_zeroes(number: int) -> int:
+    divisor: int = 5
+    zeroes_count: int = 0
+
+    while divisor <= number:
+        zeroes_count += number // divisor
+        divisor *= 5
+
+    return zeroes_count
+
+
+def copy_random_list(
+    head: stdlib.ListNodeRandom | None,
+) -> stdlib.ListNodeRandom | None:
+    if head is None:
+        return None
+
+    ordered = []
+    cur = head
+    while cur is not None:
+        ordered.append(cur)
+        cur = cur.next
+
+    ordered_copy = [stdlib.ListNodeRandom(entry.val) for entry in ordered]
+
+    hash_idx = {hash(n): i for i, n in enumerate(ordered)}
+
+    for i, entry in enumerate(ordered):
+        if i + 1 < len(ordered_copy):
+            ordered_copy[i].next = ordered_copy[i + 1]
+
+        if entry.random is not None:
+            ordered_copy[i].random = ordered_copy[hash_idx[hash(entry.random)]]
+
+    return ordered_copy[0]
+
+
+def sum_max_sub_array(nums: list[int]) -> int:
+    mmax = last = prev = nums[0]
+
+    for i in range(1, len(nums)):
+        prev = nums[i] + last
+        last = max(nums[i], prev)
+        mmax = max(mmax, last)
+
+    return mmax
+
+
+def sum_max_sub_array_i(nums: list[int]) -> tuple[int, int]:
+    mmax_i: int = 0
+    mmax = last = prev = nums[0]
+
+    for i in range(1, len(nums)):
+        prev = nums[i] + last
+        last = max(nums[i], prev)
+        mmax_i = i if last > mmax else mmax_i
+        mmax = max(mmax, last)
+
+    return mmax_i, mmax
+
+
+def sum_max_sub_array_accum(nums: list[int]) -> int:
+    accum: list[int] = [nums[0]]
+
+    for i in range(1, len(nums)):
+        prev: int = nums[i] + accum[-1]
+        accum.append(max(nums[i], prev))
+
+    return max(accum)
+
+
+def accum_sub_array_maxes(nums: list[int]) -> list[int]:
+    accum: list[int] = [nums[0]]
+
+    for i in range(1, len(nums)):
+        prev: int = nums[i] + accum[-1]
+        accum.append(max(nums[i], prev))
+
+    return accum
+
+
+def neighborly_node_from_list(inlist: list[list[int]]):
+    # Alias "Node" type for leetcode compat
+    Node = stdlib.NeighborlyNodeNicely
+
+    if len(inlist) == 0:
+        return None
+
+    outlist = [Node(i + 1, []) for i in range(len(inlist))]
+
+    for i in range(len(inlist)):
+        outlist[i].neighbors[:] = []
+
+        for neighbor_val in inlist[i]:
+            outlist[i].neighbors.append(outlist[neighbor_val - 1])
+
+    return outlist[0]
+
+
+def neighborly_node_to_list(node) -> list[list[int]]:
+    serialized: dict[int, list[int]] = {}
+
+    for cur in traverse_neighborly_node(node, serialized):
+        if cur is None:
+            break
+
+        serialized[cur.val] = [n.val for n in cur.neighbors]
+
+    return [v for _, v in sorted(serialized.items())]
+
+
+def traverse_neighborly_node(
+    node: stdlib.NeighborlyNodeNicely, memo: collections.abc.Container[int]
+) -> typing.Iterator[stdlib.NeighborlyNodeNicely | None]:
+    yield node
+
+    if node is None:
+        return
+
+    for neighbor in node.neighbors:
+        if neighbor.val in memo:
+            continue
+
+        yield from traverse_neighborly_node(neighbor, memo)
+
+
+def find_min_in_rotated_array(nums: list[int]) -> int:
+    if nums[0] <= nums[-1]:
+        return nums[0]
+
+    if len(nums) <= 3:
+        return min(nums)
+
+    if nums[len(nums) // 2] > nums[-1]:
+        return find_min_in_rotated_array(nums[len(nums) // 2 :])
+
+    return find_min_in_rotated_array(nums[: (len(nums) // 2) + 1])

leetcode/test_roman.py

@@ -0,0 +1,15 @@
+import pytest
+
+import roman
+
+
+@pytest.mark.parametrize(
+    ("n", "expected"),
+    [
+        (3, "III"),
+        (58, "LVIII"),
+        (1994, "MCMXCIV"),
+    ],
+)
+def test_int_to_roman(n: int, expected: str):
+    assert roman.i2r(n) == expected

leetcode/test_spiral_matrix.py

@@ -0,0 +1,46 @@
+import pytest
+
+import spiral_matrix
+
+
+@pytest.mark.parametrize(
+    ("matrix", "expected"),
+    [
+        (
+            [
+                ["a", "b", "c"],
+                ["d", "e", "f"],
+                ["g", "h", "i"],
+            ],
+            ["a", "b", "c", "f", "i", "h", "g", "d", "e"],
+        ),
+        (
+            [
+                [1, 2, 3, 4],
+                [5, 6, 7, 8],
+                [9, 10, 11, 12],
+            ],
+            [1, 2, 3, 4, 8, 12, 11, 10, 9, 5, 6, 7],
+        ),
+        (
+            [
+                [1, 2, 3, 4, 5, 6, 7, 8, 9],
+                [1, 2, 3, 4, 5, 6, 7, 8, 9],
+                [1, 2, 3, 4, 5, 6, 7, 8, 9],
+                [1, 2, 3, 4, 5, 6, 7, 8, 9],
+                [1, 2, 3, 4, 5, 6, 7, 8, 9],
+            ],
+            []  # noqa
+            + [1, 2, 3, 4, 5, 6, 7, 8, 9]  # right
+            + [9, 9, 9]  # down
+            + [9, 8, 7, 6, 5, 4, 3, 2, 1]  # left
+            + [1, 1]  # up
+            + [1, 2, 3, 4, 5, 6, 7, 8]  # right
+            + [8]  # down
+            + [8, 7, 6, 5, 4, 3, 2]  # left
+            + [2, 3, 4, 5, 6, 7],  # right
+        ),
+    ],
+)
+def test_matrix_spiral(matrix, expected):
+    assert spiral_matrix.matrix_spiral(matrix) == expected

leetcode/test_stuff.py

@@ -0,0 +1,505 @@
+import json
+
+import pytest
+
+import stuff
+import stdlib
+
+
+@pytest.mark.parametrize(
+    ("n", "expected"),
+    [
+        (0, 0),
+        (1, 1),
+        (5, 2),
+        (4, 2),
+        (8, 2),
+        (9, 3),
+    ],
+)
+def test_find_sqrt_ish(n: int, expected: int):
+    assert stuff.find_sqrt_ish(n) == expected
+
+
+@pytest.mark.parametrize(
+    ("ops", "expected"),
+    [
+        (
+            (
+                [
+                    ("new",),
+                    ("push", -2),
+                    ("push", 0),
+                    ("push", -3),
+                    ("getMin",),
+                    ("pop",),
+                    ("top",),
+                    ("getMin",),
+                ]
+            ),
+            [
+                None,
+                None,
+                None,
+                None,
+                -3,
+                None,
+                0,
+                -2,
+            ],
+        )
+    ],
+)
+def test_min_stack(ops: list[tuple[str] | tuple[str, int]], expected: list[int | None]):
+    returned: list[int | None] = []
+    inst: stuff.MinStack | None = None
+
+    for op in ops:
+        if len(op) == 1:
+            if op[0] == "new":
+                inst = stuff.MinStack()
+                returned.append(None)
+                continue
+
+            returned.append(getattr(inst, op[0])())
+            continue
+
+        method, arg = op
+        returned.append(getattr(inst, method)(arg))
+
+    assert returned == expected
+
+
+@pytest.mark.parametrize(
+    ("head", "expected"),
+    [
+        (None, None),
+        (
+            stdlib.ListNode(
+                4, stdlib.ListNode(2, stdlib.ListNode(1, stdlib.ListNode(3)))
+            ),
+            stdlib.ListNode(
+                1, stdlib.ListNode(2, stdlib.ListNode(3, stdlib.ListNode(4)))
+            ),
+        ),
+        (
+            stdlib.ListNode(
+                4,
+                stdlib.ListNode(
+                    19,
+                    stdlib.ListNode(
+                        14,
+                        stdlib.ListNode(
+                            5,
+                            stdlib.ListNode(
+                                -3,
+                                stdlib.ListNode(
+                                    1,
+                                    stdlib.ListNode(
+                                        8,
+                                        stdlib.ListNode(
+                                            5, stdlib.ListNode(11, stdlib.ListNode(15))
+                                        ),
+                                    ),
+                                ),
+                            ),
+                        ),
+                    ),
+                ),
+            ),
+            stdlib.ListNode(
+                -3,
+                stdlib.ListNode(
+                    1,
+                    stdlib.ListNode(
+                        4,
+                        stdlib.ListNode(
+                            5,
+                            stdlib.ListNode(
+                                5,
+                                stdlib.ListNode(
+                                    8,
+                                    stdlib.ListNode(
+                                        11,
+                                        stdlib.ListNode(
+                                            14, stdlib.ListNode(15, stdlib.ListNode(19))
+                                        ),
+                                    ),
+                                ),
+                            ),
+                        ),
+                    ),
+                ),
+            ),
+        ),
+    ],
+)
+def test_sort_linked_list(
+    head: stdlib.LinkedListNode | None, expected: stdlib.LinkedListNode | None
+):
+    if head is None:
+        assert stuff.sort_linked_list(head) == expected
+        return
+
+    assert stuff.linked_list_to_list(
+        stuff.sort_linked_list(head)
+    ) == stuff.linked_list_to_list(expected)
+
+
+@pytest.mark.parametrize(
+    ("root", "expected"),
+    [
+        (
+            stdlib.Node(
+                1,
+                left=stdlib.Node(2, left=stdlib.Node(4), right=stdlib.Node(5)),
+                right=stdlib.Node(3, right=stdlib.Node(7)),
+            ),
+            [1, None, 2, 3, None, 4, 5, 7, None],
+        ),
+    ],
+)
+def test_connect_binary_tree_right(
+    root: stdlib.ConnectableBinaryTreeNode | None, expected: list[int | None] | None
+):
+    if expected is None:
+        assert root is None
+        return
+
+    connected, serialized = stuff.connect_binary_tree_right(root)
+    assert connected is not None
+    assert serialized == expected
+
+
+@pytest.mark.parametrize(
+    ("root", "expected"),
+    [
+        (
+            stdlib.Node(
+                4,
+                right=stdlib.Node(0),
+                left=stdlib.Node(9, right=stdlib.Node(1), left=stdlib.Node(5)),
+            ),
+            1026,
+        ),
+    ],
+)
+def test_connect_binary_tree_sum_numbers(
+    root: stdlib.BinaryTreeNode | None, expected: int
+):
+    assert stuff.sum_binary_tree_path_ints(root) == expected
+
+
+@pytest.mark.parametrize(
+    ("inlist", "expected"),
+    [
+        (
+            [3, 5, 1, 6, 2, 0, 8, None, None, 7, 4],
+            stdlib.TreeNode(
+                3,
+                left=stdlib.TreeNode(
+                    5,
+                    left=stdlib.TreeNode(6),
+                    right=stdlib.TreeNode(
+                        2,
+                        left=stdlib.TreeNode(7),
+                        right=stdlib.TreeNode(4),
+                    ),
+                ),
+                right=stdlib.TreeNode(
+                    1,
+                    left=stdlib.TreeNode(0),
+                    right=stdlib.TreeNode(8),
+                ),
+            ),
+        ),
+    ],
+)
+def test_binary_tree_from_list(
+    inlist: list[int | None], expected: stdlib.BinaryTreeNode | None
+):
+    assert stuff.binary_tree_from_list(inlist) == expected
+
+
+@pytest.mark.parametrize(
+    ("preorder", "inorder", "expected"),
+    [
+        (
+            [3, 9, 20, 15, 7],
+            [9, 3, 15, 20, 7],
+            stdlib.TreeNode(
+                3,
+                left=stdlib.TreeNode(9),
+                right=stdlib.TreeNode(
+                    20, left=stdlib.TreeNode(15), right=stdlib.TreeNode(7)
+                ),
+            ),
+        ),
+        (
+            [-1],
+            [-1],
+            stdlib.TreeNode(-1),
+        ),
+        (
+            [1, 2],
+            [1, 2],
+            stdlib.TreeNode(1, right=stdlib.TreeNode(2)),
+        ),
+    ],
+)
+def test_binary_tree_from_preorder_inorder(
+    preorder: list[int], inorder: list[int], expected: stdlib.BinaryTreeNode
+):
+    assert stuff.binary_tree_from_preorder_inorder(preorder, inorder) == expected
+
+
+@pytest.mark.parametrize(
+    ("board", "expected"),
+    [
+        (
+            [2, 3, 1, 1, 4],
+            [
+                [0, 1, 2, 3, 4],
+                [0, 1, 3, 4],
+                [0, 1, 4],
+                [0, 2, 3, 4],
+            ],
+        ),
+    ],
+)
+def test_collect_complete_jump_paths_from_board(
+    board: list[int], expected: list[list[int]]
+):
+    assert list(sorted(stuff.collect_complete_jump_paths_from_board(board))) == expected
+
+
+@pytest.mark.parametrize(
+    ("board", "expected"),
+    [
+        (
+            [2, 3, 1, 1, 4],
+            2,
+        ),
+        (
+            [2, 3, 0, 1, 4],
+            2,
+        ),
+        (
+            [1],
+            0,
+        ),
+        (
+            [1, 2],
+            1,
+        ),
+        (
+            [6, 2, 6, 1, 7, 9, 3, 5, 3, 7, 2, 8, 9, 4, 7, 7, 2, 2, 8, 4, 6, 6, 1, 3],
+            4,
+        ),
+        (
+            [3, 4, 3, 2, 5, 4, 3],
+            3,
+        ),
+        (
+            [3, 2, 1],
+            1,
+        ),
+        (
+            [1, 2, 3],
+            2,
+        ),
+    ],
+)
+def test_count_min_jumps_from_board(board: list[int], expected: int):
+    assert stuff.count_min_jumps_from_board(board) == expected
+
+
+@pytest.mark.parametrize(
+    ("citations", "expected"),
+    [
+        (
+            [3, 0, 6, 1, 5],
+            3,
+        ),
+        (
+            [1, 3, 1],
+            1,
+        ),
+        (
+            [100],
+            1,
+        ),
+    ],
+)
+def test_h_index(citations: list[int], expected: int):
+    assert stuff.h_index(citations) == expected
+
+
+@pytest.mark.parametrize(
+    ("cls",),
+    [
+        (stuff.SlowRandomizedSet,),
+        (stuff.RandomizedSet,),
+    ],
+)
+def test_randomized_set(cls: type[stuff.RandomizedSet] | type[stuff.SlowRandomizedSet]):
+    inst = cls()
+
+    assert inst.insert(1) is True
+    assert inst.remove(2) is False
+    assert inst.insert(2) is True
+    assert inst.getRandom() in (1, 2)
+    assert inst.remove(1) is True
+    assert inst.insert(2) is False
+    assert inst.getRandom() == 2
+
+    inst = cls()
+
+    assert inst.insert(1) is True
+    assert inst.insert(10) is True
+    assert inst.insert(20) is True
+    assert inst.insert(30) is True
+
+    seen: set[int] = set()
+
+    for _ in range(10_000):
+        seen.add(inst.getRandom())
+
+    assert seen == {1, 10, 20, 30}
+
+    # ["remove","remove","insert","getRandom","remove","insert"]
+    # [[0],[0],[0],[],[0],[0]]
+
+    inst = cls()
+
+    assert inst.remove(0) is False
+    assert inst.remove(0) is False
+    assert inst.insert(0) is True
+    assert inst.getRandom() == 0
+    assert inst.remove(0) is True
+    assert inst.insert(0) is True
+
+    # ["RandomizedSet","insert","insert","remove","insert","remove","getRandom"]
+    # [[],[0],[1],[0],[2],[1],[]]
+
+    inst = cls()
+
+    assert inst.insert(0) is True
+    assert inst.insert(1) is True
+    assert inst.remove(0) is True
+    assert inst.insert(2) is True
+    assert inst.remove(1) is True
+    assert inst.getRandom() == 2
+
+
+def test_trie_single_letter():
+    trie = stuff.Trie()
+
+    assert trie.insert("a") is None
+    assert trie.search("a") is True
+    assert trie.startsWith("a") is True
+
+
+def test_trie_prefix_leaf():
+    trie = stuff.Trie()
+
+    assert trie.insert("apple") is None
+    assert trie.search("apple") is True
+    assert trie.search("app") is False
+    assert trie.startsWith("app") is True
+    assert trie.insert("app") is None
+    assert trie.search("app") is True
+
+
+def test_trie_two_letter():
+    trie = stuff.Trie()
+
+    assert trie.insert("ab") is None
+    assert trie.search("a") is False
+    assert trie.startsWith("a") is True
+
+
+def test_trie_busy():
+    trie = stuff.Trie()
+
+    assert trie.insert("app") is None
+    assert trie.insert("apple") is None
+    assert trie.insert("beer") is None
+    assert trie.insert("add") is None
+    assert trie.insert("jam") is None
+    assert trie.insert("rental") is None
+    assert trie.search("apps") is False
+    assert trie.search("app") is True
+    assert trie.search("ad") is False
+    assert trie.search("applepie") is False
+    assert trie.search("rest") is False
+    assert trie.search("jan") is False
+    assert trie.search("rent") is False
+    assert trie.search("beer") is True
+    assert trie.search("jam") is True
+    assert trie.startsWith("apps") is False
+    assert trie.startsWith("app") is True
+    assert trie.startsWith("ad") is True
+    assert trie.startsWith("applepie") is False
+    assert trie.startsWith("rest") is False
+    assert trie.startsWith("jan") is False
+    assert trie.startsWith("rent") is True
+    assert trie.startsWith("beer") is True
+    assert trie.startsWith("jam") is True
+
+
+@pytest.mark.parametrize(
+    ("nums", "expected"),
+    [
+        (
+            [-2, 1, -3, 4, -1, 2, 1, -5, 4],
+            6,
+        ),
+        (
+            [1],
+            1,
+        ),
+        (
+            [5, 4, -1, 7, 8],
+            23,
+        ),
+        (
+            [-2, 1],
+            1,
+        ),
+        (
+            json.load(open(".testdata/max_sub_array0.json")),
+            11081,
+        ),
+    ],
+)
+def test_max_sub_array(nums: list[int], expected: int):
+    assert stuff.sum_max_sub_array(nums) == expected
+
+
+@pytest.mark.parametrize(
+    ("inlist",),
+    [
+        ([[2, 3, 4], [1, 7], [1], [1, 5, 6, 8], [4], [4], [2], [4]],),
+        ([[2, 4], [1, 3], [2, 4], [1, 3]],),
+    ],
+)
+def test_copy_neighborly_node(inlist):
+    orig = stuff.neighborly_node_from_list(inlist)
+    copied = stuff.neighborly_node_from_list(stuff.neighborly_node_to_list(orig))
+
+    assert id(orig) != id(copied)
+    assert orig == copied
+    assert stuff.neighborly_node_to_list(orig) == stuff.neighborly_node_to_list(copied)
+
+
+@pytest.mark.parametrize(
+    ("nums", "expected"),
+    [
+        ([3, 4, 5, 1, 2], 1),
+        ([4, 5, 6, 7, 0, 1, 2], 0),
+        ([11, 13, 15, 17], 11),
+    ],
+)
+def test_find_min_in_rotated_array(nums: list[int], expected: int):
+    assert stuff.find_min_in_rotated_array(nums) == expected

modernc/01/.gitignore

@@ -0,0 +1 @@
+getting-started

modernc/01/bad.c

@@ -0,0 +1,23 @@
+/* This may look like nonsense, but really is -*- mode: C -*- */
+
+/* The main thing that this program does. */
+void main() {
+  // Decralations
+  int i;
+  double A[5] = {
+	9.0,
+	2.9,
+	3.E+25,
+	.00007,
+  };
+
+  // Doing some work
+  for (i = 0; i < 5; ++i) {
+	printf("element %d is %g, \tits square is %g\n",
+		i,
+		A[i],
+		A[i]*A[i]);
+  }
+
+  return 0;
+}

modernc/01/getting-started.c

@@ -0,0 +1,24 @@
+/* This may look like nonsense, but really is -*- mode: C -*- */
+#include <stdlib.h>
+#include <stdio.h>
+
+/* The main thing that this program does. */
+int main(void) {
+  // Decralations
+  double A[5] = {
+    [0] = 9.0,
+    [1] = 2.9,
+    [4] = 3.E+25,
+    [3] = .00007,
+  };
+
+  // Doing some work
+  for (size_t i = 0; i < 5; ++i) {
+    printf("element %zu is %g, \tits square is %g\n",
+        i,
+        A[i],
+        A[i]*A[i]);
+  }
+
+  return EXIT_SUCCESS;
+}

modernc/03/.gitignore

@@ -0,0 +1,2 @@
+challenge-1
+heron

modernc/03/array.c

@@ -0,0 +1,90 @@
+#include <stdlib.h>
+#include "array.h"
+
+void IntArray_new(IntArray* a, size_t size) {
+	a->arr = malloc(size * sizeof(int));
+	a->used = 0;
+	a->size = size;
+}
+
+int IntArray_append(IntArray* a, int el) {
+	if (a->used == a->size) {
+		a->size *= 2;
+		a->arr = realloc(a->arr, a->size * sizeof(int));
+	}
+
+	a->used++;
+
+	a->arr[a->used] = el;
+	return a->used;
+}
+
+int IntArray_get(IntArray* a, int idx, int dflt) {
+	if (idx > a->used) {
+		return dflt;
+	}
+
+	return a->arr[idx];
+}
+
+int IntArray_length(IntArray* a) {
+	return a->used;
+}
+
+void IntArray_mergesort(IntArray* a) {
+	IntArray left_side;
+	IntArray right_side;
+
+	size_t split = a->used / 2;
+
+	IntArray_new(&left_side, split);
+	IntArray_new(&right_side, split);
+
+	for (int i = 0; i < split; ++i) {
+		IntArray_append(&left_side, IntArray_get(a, i, 0));
+	}
+
+	for (int i = split; i < a->used; ++i) {
+		IntArray_append(&right_side, IntArray_get(a, i, 0));
+	}
+
+	IntArray_mergesort(&left_side);
+	IntArray_mergesort(&right_side);
+
+	IntArray_mergesort_merge(a, &left_side, &right_side);
+}
+
+void IntArray_mergesort_merge(IntArray* a, IntArray* left_side, IntArray* right_side) {
+	IntArray_free(a);
+
+	size_t i = 0;
+	size_t j = 0;
+
+	while (i < left_side->used && j < right_side->used) {
+		if (left_side->arr[i] <= right_side->arr[j]) {
+			IntArray_append(a, left_side->arr[i]);
+			i++;
+		} else {
+			IntArray_append(a, right_side->arr[j]);
+			j++;
+		}
+	}
+
+	for (size_t li = 0; li < left_side->used; ++li) {
+		IntArray_append(a, left_side->arr[li]);
+	}
+
+	for (size_t ri = 0; ri < right_side->used; ++ri) {
+		IntArray_append(a, right_side->arr[ri]);
+	}
+}
+
+void IntArray_quicksort(IntArray* a) {
+	return;
+}
+
+void IntArray_free(IntArray* a) {
+	free(a->arr);
+	a->arr = NULL;
+	a->used = a->size = 0;
+}

modernc/03/array.h

@@ -0,0 +1,22 @@
+#ifndef INCLUDED_ARRAY_H
+#include <stdlib.h>
+
+typedef struct {
+    int *arr;
+    size_t used;
+    size_t size;
+} IntArray;
+
+void IntArray_new(IntArray*, size_t);
+
+int IntArray_append(IntArray*, int);
+int IntArray_get(IntArray*, int, int);
+int IntArray_length(IntArray*);
+void IntArray_mergesort(IntArray*);
+void IntArray_mergesort_merge(IntArray*, IntArray*, IntArray*);
+void IntArray_quicksort(IntArray*);
+
+void IntArray_free(IntArray*);
+
+#define INCLUDED_ARRAY_H 1
+#endif

modernc/03/challenge-1.c

@@ -0,0 +1,114 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <getopt.h>
+#include <string.h>
+
+#include "array.h"
+
+#define IODASH "-"
+
+void usage(char* prog) {
+	fprintf(stderr, "Usage: %s [-f|--input-file <input-file>] [-o|--output-file <output-file>]\n", prog);
+}
+
+int main(int argc, char **argv) {
+	char* input_file = IODASH;
+	char* output_file = IODASH;
+
+	int c = 0;
+
+	while (1) {
+		static struct option long_options[] = {
+			{"input-file", required_argument, 0, 'f'},
+			{"output-file", required_argument, 0, 'o'},
+		};
+
+		int option_index = 0;
+
+		c = getopt_long(argc, argv, "f:o:", long_options, &option_index);
+
+		if (c == -1) {
+			break;
+		}
+
+		switch (c) {
+		case 'f':
+			input_file = optarg;
+			break;
+		case 'o':
+			output_file = optarg;
+			break;
+		default:
+			usage(argv[0]);
+			return 1;
+		}
+	}
+
+	if (strcmp(input_file, IODASH) == 0) {
+		fprintf(stderr, "(reading from stdin)\n");
+	}
+
+	if (strcmp(output_file, IODASH) == 0) {
+		fprintf(stderr, "(writing to stdout)\n");
+	}
+
+	printf("input_file='%s' output_file='%s'\n", input_file, output_file);
+
+	FILE* instream;
+
+	instream = stdin;
+	if (strcmp(input_file, IODASH) != 0) {
+		instream = fopen(input_file, "r");
+	}
+
+	if (instream == NULL) {
+		perror("opening input file");
+		return EXIT_FAILURE;
+	}
+
+	FILE* outstream;
+
+	outstream = stdout;
+	if (strcmp(output_file, IODASH) != 0) {
+		outstream = fopen(output_file, "r");
+	}
+
+	if (outstream == NULL) {
+		perror("opening output file");
+		return EXIT_FAILURE;
+	}
+
+	int line_int;
+	ssize_t nread;
+
+	char* endptr = NULL;
+	char* line = NULL;
+	size_t len = 0;
+
+	IntArray accum;
+	IntArray_new(&accum, 100);
+
+	while ((nread = getline(&line, &len, instream)) != -1) {
+		IntArray_append(&accum, atoi(line));
+	}
+
+	printf("Accumulated %i ints\n", IntArray_length(&accum));
+
+	IntArray_mergesort(&accum);
+
+	printf("Merge sorted:\n");
+
+	for (int i = 0; i < accum.used; ++i) {
+		printf("%i: %i\n", i, IntArray_get(&accum, i, 0));
+	}
+
+	if (strcmp(input_file, IODASH) != 0) {
+		fclose(instream);
+	}
+
+	if (strcmp(output_file, IODASH) != 0) {
+		fclose(outstream);
+	}
+
+	return EXIT_SUCCESS;
+}

modernc/03/heron.c

@@ -0,0 +1,40 @@
+#include <stdlib.h>
+#include <stdio.h>
+
+/* lower and upper iteration limits centered around 1.0 */
+static double const eps1m01 = 1.0 - 0x1P-01;
+static double const eps1p01 = 1.0 + 0x1P-01;
+static double const eps1m24 = 1.0 - 0x1P-24;
+static double const eps1p24 = 1.0 + 0x1P-24;
+
+int main(int argc, char* argv[argc+1]) {
+	for (int i = 1; i < argc; ++i) {
+		double const a = strtod(argv[i], 0);
+		double x = 1.0;
+
+		for (;;) {
+			double prod = a*x;
+			if (prod < eps1m01) {
+				x *= 2.0;
+			} else if (eps1p01 < prod) {
+				x *= 0.5;
+			} else {
+				break;
+			}
+		}
+
+		for (;;) {
+			double prod = a*x;
+			if ((prod < eps1m24) || (eps1p24 < prod)) {
+				x *= (2.0 - prod);
+			} else {
+				break;
+			}
+		}
+
+		printf("heron: a=%.5e,\tx=%.5e,\ta*x=%.12f\n",
+				a, x, a*x);
+	}
+
+	return EXIT_SUCCESS;
+}

modernc/05/.gitignore

@@ -0,0 +1 @@
+basic

modernc/05/basic.c

@@ -0,0 +1,9 @@
+#include <stdio.h>
+
+int main() {
+	double x = 5.0;
+	double y = 3.0;
+
+	x = (x * 1.5) - y;
+	printf("x is \%g\n", x);
+}

personal-home-page/.gitignore

@@ -0,0 +1 @@
+/vendor/

personal-home-page/blergh.php

@@ -0,0 +1,11 @@
+<?php
+
+require_once 'vendor/autoload.php';
+
+$hello_cmd = new Commando\Command();
+
+$hello_cmd->option()->require()->describedAs('A person\'s name');
+
+$name = $hello_cmd[0];
+
+echo "Hello, $name", PHP_EOL;

personal-home-page/composer.json

@@ -0,0 +1,14 @@
+{
+    "name": "meatballhat/personal-home-page",
+    "type": "library",
+    "require": {
+        "nategood/commando": "^0.4.0"
+    },
+    "license": "MIT",
+    "authors": [
+        {
+            "name": "Dan Buch",
+            "email": "dan@meatballhat.com"
+        }
+    ]
+}

personal-home-page/composer.lock

@@ -0,0 +1,124 @@
+{
+    "_readme": [
+        "This file locks the dependencies of your project to a known state",
+        "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
+        "This file is @generated automatically"
+    ],
+    "content-hash": "4aa26239cdb17b13a548c56ac84b5749",
+    "packages": [
+        {
+            "name": "kevinlebrun/colors.php",
+            "version": "0.4.1",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/kevinlebrun/colors.php.git",
+                "reference": "d132f36d06e48ea080855af19b4bcb1fb615224a"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/kevinlebrun/colors.php/zipball/d132f36d06e48ea080855af19b4bcb1fb615224a",
+                "reference": "d132f36d06e48ea080855af19b4bcb1fb615224a",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=5.3.0"
+            },
+            "require-dev": {
+                "phpunit/phpunit": "3.7.*",
+                "satooshi/php-coveralls": "dev-master",
+                "squizlabs/php_codesniffer": "1.*"
+            },
+            "type": "library",
+            "autoload": {
+                "psr-0": {
+                    "Colors": "src/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Kevin Le Brun",
+                    "email": "lebrun.k@gmail.com",
+                    "homepage": "http://kevinlebrun.fr",
+                    "role": "developer"
+                }
+            ],
+            "description": "Colors for PHP CLI scripts",
+            "homepage": "https://github.com/kevinlebrun/colors.php",
+            "keywords": [
+                "cli",
+                "color",
+                "colors",
+                "console",
+                "shell"
+            ],
+            "support": {
+                "issues": "https://github.com/kevinlebrun/colors.php/issues",
+                "source": "https://github.com/kevinlebrun/colors.php/tree/0.4.1"
+            },
+            "time": "2014-12-23T01:23:37+00:00"
+        },
+        {
+            "name": "nategood/commando",
+            "version": "0.4.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/nategood/commando.git",
+                "reference": "8fedd49fcb694faf60d87d5c2c4defdffa298fa0"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/nategood/commando/zipball/8fedd49fcb694faf60d87d5c2c4defdffa298fa0",
+                "reference": "8fedd49fcb694faf60d87d5c2c4defdffa298fa0",
+                "shasum": ""
+            },
+            "require": {
+                "kevinlebrun/colors.php": "~0.2",
+                "php": ">=5.6"
+            },
+            "type": "library",
+            "autoload": {
+                "psr-0": {
+                    "Commando": "src/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Nate Good",
+                    "email": "me@nategood.com"
+                }
+            ],
+            "description": "PHP CLI Commando Style",
+            "homepage": "http://github.com/nategood/commando",
+            "keywords": [
+                "automation",
+                "cli",
+                "command",
+                "command line",
+                "command line interface",
+                "scripting"
+            ],
+            "support": {
+                "issues": "https://github.com/nategood/commando/issues",
+                "source": "https://github.com/nategood/commando/tree/v0.4.0"
+            },
+            "time": "2019-07-10T02:37:11+00:00"
+        }
+    ],
+    "packages-dev": [],
+    "aliases": [],
+    "minimum-stability": "stable",
+    "stability-flags": [],
+    "prefer-stable": false,
+    "prefer-lowest": false,
+    "platform": [],
+    "platform-dev": [],
+    "plugin-api-version": "2.6.0"
+}

personal-home-page/hello.php

@@ -0,0 +1,11 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <title>Example</title>
+  </head>
+  <body>
+    <?php
+      echo "<h3>Hi, I'm a PHP script!</h3>";
+    ?>
+  </body>
+</html>

personal-home-page/helloworld.php

@@ -0,0 +1,35 @@
+<?php
+
+$name = 'Flavio';
+
+var_dump($name);
+
+$age = 20;
+
+var_dump($age);
+
+$base = 20;
+$height = 10;
+
+$area = $base * $height;
+
+$test = 'an example';
+
+$example = "This is $test";
+
+print $example . "\n";
+
+$firstName = 'Flavio';
+$lastName = 'Copes';
+
+$fullName = $firstName . ' ' . $lastName;
+
+print '$fullName = ' . $fullName . "\n";
+
+print strlen($fullName) . "\n";
+
+$weirdName = str_replace('avio', 'ower', $fullName);
+
+print '$weirdName = ' . $weirdName . "\n";
+
+print 'exploded $weirdName = ' . var_dump(explode(' ', $weirdName)) . "\n";

personal-home-page/phpinfo.php

@@ -0,0 +1 @@
+<?php phpinfo(); ?>

personal-home-page/pong.php

@@ -0,0 +1,6 @@
+<pre>
+<?php
+echo $_SERVER['HTTP_USER_AGENT'], PHP_EOL;
+var_dump($_SERVER);
+?>
+</pre>

rustbyexample/.gitignore

@@ -1,11 +1,3 @@
-/custom_types/*
-/hello/*
-/primitives/*
-/variable_bindings/*
-/types/*
-
-!/custom_types/*.rs
-!/hello/*.rs
-!/primitives/*.rs
-!/variable_bindings/*.rs
-!/types/*.rs
+/out/
+/*.d/out
+/*.d/**/out

rustbyexample/conversion.d/from_into.rs

@@ -0,0 +1,18 @@
+use std::convert::From;
+
+#[allow(dead_code)]
+#[derive(Debug)]
+struct Number {
+    value: i32,
+}
+
+impl From<i32> for Number {
+    fn from(item: i32) -> Self {
+        Number { value: item }
+    }
+}
+
+fn main() {
+    let num = Number::from(30);
+    println!("My number is {:?}", num);
+}

rustbyexample/conversion.d/from_into2.rs

@@ -0,0 +1,19 @@
+use std::convert::Into;
+
+#[allow(dead_code)]
+#[derive(Debug)]
+struct Number {
+    value: i32,
+}
+
+impl Into<Number> for i32 {
+    fn into(self) -> Number {
+        Number { value: self }
+    }
+}
+
+fn main() {
+    let int = 5;
+    let num: Number = int.into();
+    println!("My number is {:?}", num);
+}

rustbyexample/conversion.d/string.rs

@@ -0,0 +1,16 @@
+use std::fmt;
+
+struct Circle {
+    radius: i32,
+}
+
+impl fmt::Display for Circle {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "Circle of radius {}", self.radius)
+    }
+}
+
+fn main() {
+    let circle = Circle { radius: 6 };
+    println!("{}", circle.to_string());
+}

rustbyexample/conversion.d/string2.rs

@@ -0,0 +1,7 @@
+fn main() {
+    let parsed: i32 = "5".parse().unwrap();
+    let turbo_parsed = "10".parse::<i32>().unwrap();
+
+    let sum = parsed + turbo_parsed;
+    println!("Sum: {:?}", sum);
+}

rustbyexample/conversion.d/try_from_try_into.rs

@@ -0,0 +1,28 @@
+use std::convert::TryFrom;
+use std::convert::TryInto;
+
+#[derive(Debug, PartialEq)]
+struct EvenNumber(i32);
+
+impl TryFrom<i32> for EvenNumber {
+    type Error = ();
+
+    fn try_from(value: i32) -> Result<Self, Self::Error> {
+        if value % 2 == 0 {
+            Ok(EvenNumber(value))
+        } else {
+            Err(())
+        }
+    }
+}
+
+fn main() {
+    assert_eq!(EvenNumber::try_from(8), Ok(EvenNumber(8)));
+    assert_eq!(EvenNumber::try_from(5), Err(()));
+
+    let result: Result<EvenNumber, ()> = 8i32.try_into();
+    assert_eq!(result, Ok(EvenNumber(8)));
+
+    let result: Result<EvenNumber, ()> = 5i32.try_into();
+    assert_eq!(result, Err(()));
+}

rustbyexample/custom_types.d/structs.rs

@@ -1,3 +1,4 @@
+#[allow(dead_code)]
 #[derive(Debug)]
 struct Person {
     name: String,

rustbyexample/expression.rs

@@ -0,0 +1,25 @@
+#[allow(path_statements)]
+#[allow(unused_must_use)]
+fn main() {
+    let x = 5;
+    x;
+    x + 1;
+    15;
+
+    let x = 5u32;
+
+    let y = {
+        let x_squared = x * x;
+        let x_cube = x_squared * x;
+
+        x_cube + x_squared + x
+    };
+
+    let z = {
+        2 * x;
+    };
+
+    println!("x is {:?}", x);
+    println!("y is {:?}", y);
+    println!("z is {:?}", z);
+}

rustbyexample/flow_control.d/for.rs

@@ -0,0 +1,13 @@
+fn main() {
+    for n in 1..101 {
+        if n % 15 == 0 {
+            println!("fizzbuzz");
+        } else if n % 3 == 0 {
+            println!("fizz");
+        } else if n % 5 == 0 {
+            println!("buzz");
+        } else {
+            println!("{}", n);
+        }
+    }
+}

rustbyexample/flow_control.d/for2.rs

@@ -0,0 +1,13 @@
+fn main() {
+    for n in 1..=100 {
+        if n % 15 == 0 {
+            println!("fizzbuzz");
+        } else if n % 3 == 0 {
+            println!("fizz");
+        } else if n % 5 == 0 {
+            println!("buzz");
+        } else {
+            println!("{}", n);
+        }
+    }
+}

rustbyexample/flow_control.d/for3.rs

@@ -0,0 +1,12 @@
+fn main() {
+    let names = vec!["Bob", "Frank", "Ferris"];
+
+    for name in names.iter() {
+        match name {
+            &"Ferris" => println!("There is a rustacean among us!"),
+            _ => println!("Hello {}", name),
+        }
+    }
+
+    println!("names: {:?}", names);
+}

rustbyexample/flow_control.d/for4.rs

@@ -0,0 +1,12 @@
+fn main() {
+    let names = vec!["Bob", "Frank", "Ferris"];
+
+    for name in names.into_iter() {
+        match name {
+            "Ferris" => println!("There is a rustacean among us!"),
+            _ => println!("Hello {}", name),
+        }
+    }
+
+    //println!("names: {:?}", names);
+}

rustbyexample/flow_control.d/for5.rs

@@ -0,0 +1,12 @@
+fn main() {
+    let mut names = vec!["Bob", "Frank", "Ferris"];
+
+    for name in names.iter_mut() {
+        *name = match name {
+            &mut "Ferris" => "There is a rustacean among us!",
+            _ => "Hello",
+        }
+    }
+
+    println!("names: {:?}", names);
+}

rustbyexample/flow_control.d/if_else.rs

@@ -0,0 +1,23 @@
+fn main() {
+    let n = 5;
+
+    if n < 0 {
+        print!("{} is negative", n);
+    } else if n > 0 {
+        print!("{} is positive", n);
+    } else {
+        print!("{} is zero", n);
+    }
+
+    let big_n = if n < 10 && n > -10 {
+        println!(", and is a small number, increase net-fold");
+
+        10 * n
+    } else {
+        println!(", and is a big number, halve the number");
+
+        n / 2
+    };
+
+    println!("{} -> {}", n, big_n);
+}

rustbyexample/flow_control.d/if_let.rs

@@ -0,0 +1,25 @@
+fn main() {
+    let number = Some(7);
+    let letter: Option<i32> = None;
+    let emoticon: Option<i32> = None;
+
+    if let Some(i) = number {
+        println!("Matched {:?}!", i);
+    }
+
+    if let Some(i) = letter {
+        println!("Matched {:?}!", i);
+    } else {
+        println!("Didn't match a number. Let's go with a letter!");
+    }
+
+    let i_like_letters = false;
+
+    if let Some(i) = emoticon {
+        println!("Matched {:?}!", i);
+    } else if i_like_letters {
+        println!("Didn't match a number. Let's go with a letter!");
+    } else {
+        println!("I don't like letters. Let's go with an emoticon :)!");
+    }
+}

rustbyexample/flow_control.d/if_let2.rs

@@ -0,0 +1,27 @@
+enum Foo {
+    Bar,
+    Baz,
+    Qux(u32),
+}
+
+fn main() {
+    let a = Foo::Bar;
+    let b = Foo::Baz;
+    let c = Foo::Qux(100);
+
+    if let Foo::Bar = a {
+        println!("a is a foobar");
+    }
+
+    if let Foo::Bar = b {
+        println!("b is foobar");
+    }
+
+    if let Foo::Qux(value) = c {
+        println!("c is {}", value);
+    }
+
+    if let Foo::Qux(value @ 100) = c {
+        println!("c is one hundred (value: {:?})", value);
+    }
+}

rustbyexample/flow_control.d/if_let3.rs

@@ -0,0 +1,11 @@
+enum Foo {
+    Bar,
+}
+
+fn main() {
+    let a = Foo::Bar;
+
+    if let Foo::Bar = a {
+        println!("a is foobar");
+    }
+}

rustbyexample/flow_control.d/let_else.rs

@@ -0,0 +1,16 @@
+use std::str::FromStr;
+
+fn get_count_item(s: &str) -> (u64, &str) {
+    let mut it = s.split(' ');
+    let (Some(count_str), Some(item)) = (it.next(), it.next()) else {
+        panic!("Can't segment count item pair: '{s}'");
+    };
+    let Ok(count) = u64::from_str(count_str) else {
+        panic!("Can't parse integer: '{count_str}'");
+    };
+    (count, item)
+}
+
+fn main() {
+    assert_eq!(get_count_item("3 chairs"), (3, "chairs"));
+}

rustbyexample/flow_control.d/loop.d/nested.rs

@@ -0,0 +1,18 @@
+#![allow(unreachable_code)]
+#![allow(unused_labels)]
+
+fn main() {
+    'outer: loop {
+        println!("Entered the outer loop");
+
+        'inner: loop {
+            println!("Entered the inner loop");
+
+            break 'outer;
+        }
+
+        println!("This point will never be reached");
+    }
+
+    println!("Exited the outer loop");
+}

rustbyexample/flow_control.d/loop.d/return.rs

@@ -0,0 +1,13 @@
+fn main() {
+    let mut counter = 0;
+
+    let result = loop {
+        counter += 1;
+
+        if counter == 10 {
+            break counter * 2;
+        }
+    };
+
+    assert_eq!(result, 20);
+}

rustbyexample/flow_control.d/loop.rs

@@ -0,0 +1,23 @@
+fn main() {
+    let mut count = 0u32;
+
+    println!("Let's count until infinity!");
+
+    loop {
+        count += 1;
+
+        if count == 3 {
+            println!("three");
+
+            continue;
+        }
+
+        println!("{}", count);
+
+        if count == 5 {
+            println!("OK, that's enough");
+
+            break;
+        }
+    }
+}

rustbyexample/flow_control.d/match.d/binding.rs

@@ -0,0 +1,14 @@
+fn age() -> u32 {
+    15
+}
+
+fn main() {
+    println!("Tell me what type of person you are");
+
+    match age() {
+        0 => println!("I haven't celebrated my first birthday yet"),
+        n @ 1..=12 => println!("I'm a child of age {:?}", n),
+        n @ 13..=19 => println!("I'm a teen of age {:?}", n),
+        n => println!("I'm an old person of age {:?}", n),
+    }
+}

rustbyexample/flow_control.d/match.d/binding2.rs

@@ -0,0 +1,11 @@
+fn some_number() -> Option<u32> {
+    Some(42)
+}
+
+fn main() {
+    match some_number() {
+        Some(n @ 42) => println!("The Answer: {}!", n),
+        Some(n) => println!("Not interesting... {}", n),
+        _ => (),
+    }
+}

rustbyexample/flow_control.d/match.d/destructuring.d/destructure_enum.rs

@@ -0,0 +1,30 @@
+#[allow(dead_code)]
+enum Color {
+    Red,
+    Blue,
+    Green,
+    RGB(u32, u32, u32),
+    HSV(u32, u32, u32),
+    HSL(u32, u32, u32),
+    CMY(u32, u32, u32),
+    CMYK(u32, u32, u32, u32),
+}
+
+fn main() {
+    let color = Color::RGB(122, 17, 40);
+
+    println!("What color is it?");
+    match color {
+        Color::Red => println!("The color is Red!"),
+        Color::Blue => println!("The color is Blue!"),
+        Color::Green => println!("The color is Green!"),
+        Color::RGB(r, g, b) => println!("Red: {}, green: {}, and blue: {}!", r, g, b),
+        Color::HSV(h, s, v) => println!("Hue: {}, saturation: {}, value: {}!", h, s, v),
+        Color::HSL(h, s, l) => println!("Hue: {}, saturation: {}, lightness: {}!", h, s, l),
+        Color::CMY(c, m, y) => println!("Cyan: {}, magenta: {}, yellow: {}!", c, m, y),
+        Color::CMYK(c, m, y, k) => println!(
+            "Cyan: {}, magenta: {}, yellow: {}, key (black): {}!",
+            c, m, y, k
+        ),
+    }
+}

rustbyexample/flow_control.d/match.d/destructuring.d/destructure_pointers.rs

@@ -0,0 +1,29 @@
+fn main() {
+    let reference = &4;
+
+    match reference {
+        &val => println!("Got a value via destructuring: {:?}", val),
+    }
+
+    match *reference {
+        val => println!("Got a value via dereferencing: {:?}", val),
+    }
+
+    let _not_a_reference = 3;
+
+    let ref _is_a_reference = 3;
+
+    let value = 5;
+    let mut mut_value = 6;
+
+    match value {
+        ref r => println!("Got a reference to a value: {:?}", r),
+    }
+
+    match mut_value {
+        ref mut m => {
+            *m += 10;
+            println!("We added 10. `mut_value`: {:?}", m);
+        }
+    }
+}

rustbyexample/flow_control.d/match.d/destructuring.d/destructure_slice.rs

@@ -0,0 +1,27 @@
+fn main() {
+    let array = [1, -2, 6];
+
+    match array {
+        [0, second, third] => println!("array[0] = 0, array[1] = {}, array[2] = {}", second, third),
+
+        [1, _, third] => println!(
+            "array[0] = 1, array[2] = {} and array[1] was ignored",
+            third
+        ),
+
+        [-1, second, ..] => println!(
+            "array[0] = -1, array[1] = {} and all the other ones were ignored",
+            second
+        ),
+
+        [3, second, tail @ ..] => println!(
+            "array[0] = 3, array[1] = {} and the other elements were {:?}",
+            second, tail
+        ),
+
+        [first, middle @ .., last] => println!(
+            "array[0] = {}, middle = {:?}, array[2] = {}",
+            first, middle, last
+        ),
+    }
+}

rustbyexample/flow_control.d/match.d/destructuring.d/destructure_structures.rs

@@ -0,0 +1,19 @@
+fn main() {
+    struct Foo {
+        x: (u32, u32),
+        y: u32,
+    }
+
+    let foo = Foo { x: (1, 2), y: 3 };
+
+    match foo {
+        Foo { x: (1, b), y } => println!("First of x is 1, b = {}, y = {}", b, y),
+        Foo { y: 2, x: i } => println!("y is 2, i = {:?}", i),
+        Foo { y, .. } => println!("y = {}, we don't care about x", y),
+    }
+
+    let faa = Foo { x: (1, 2), y: 3 };
+
+    let Foo { x: x0, y: y0 } = faa;
+    println!("Outside: x0 = {x0:?}, y0 = {y0}");
+}

rustbyexample/flow_control.d/match.d/destructuring.d/destructure_tuple.rs

@@ -0,0 +1,12 @@
+fn main() {
+    let triple = (0, -2, 3);
+
+    println!("Tell me about {:?}", triple);
+    match triple {
+        (0, y, z) => println!("First is `0`, `y` is {:?}, and `z` is {:?}", y, z),
+        (1, ..) => println!("First is `1` and the rest doesn't matter"),
+        (.., 2) => println!("last is `2` and the rest doesn't matter"),
+        (3, .., 4) => println!("First is `3`, last is `4`, and the rest doesn't matter"),
+        _ => println!("It doesn't matter what they are"),
+    }
+}

rustbyexample/flow_control.d/match.d/guard.rs

@@ -0,0 +1,16 @@
+#[allow(dead_code)]
+enum Temperature {
+    Celsius(i32),
+    Fahrenheit(i32),
+}
+
+fn main() {
+    let temperature = Temperature::Celsius(35);
+
+    match temperature {
+        Temperature::Celsius(t) if t > 30 => println!("{}C is above 30 Celsius", t),
+        Temperature::Celsius(t) => println!("{}C is below 30 Celsius", t),
+        Temperature::Fahrenheit(t) if t > 86 => println!("{}F is above 86 Fahrenheit", t),
+        Temperature::Fahrenheit(t) => println!("{}F is below 86 Fahrenheit", t),
+    }
+}

rustbyexample/flow_control.d/match.d/guard2.rs

@@ -0,0 +1,9 @@
+fn main() {
+    let number: u8 = 4;
+
+    match number {
+        i if i == 0 => println!("Zero"),
+        i if i > 0 => println!("Greater than zero"),
+        _ => unreachable!("Should never happen."),
+    }
+}

rustbyexample/flow_control.d/match.rs

@@ -0,0 +1,19 @@
+fn main() {
+    let number = 13;
+
+    println!("Tell me about {}", number);
+    match number {
+        1 => println!("One!"),
+        2 | 3 | 5 | 7 | 11 => println!("This is a prime"),
+        13..=19 => println!("A teen"),
+        _ => println!("Ain't special"),
+    }
+
+    let boolean = true;
+    let binary = match boolean {
+        false => 0,
+        true => 1,
+    };
+
+    println!("{} -> {}", boolean, binary);
+}

rustbyexample/flow_control.d/while.rs

@@ -0,0 +1,17 @@
+fn main() {
+    let mut n = 1;
+
+    while n < 101 {
+        if n % 15 == 0 {
+            println!("fizzbuzz");
+        } else if n % 3 == 0 {
+            println!("fizz");
+        } else if n % 5 == 0 {
+            println!("buzz");
+        } else {
+            println!("{}", n);
+        }
+
+        n += 1;
+    }
+}

rustbyexample/flow_control.d/while_let.rs

@@ -0,0 +1,13 @@
+fn main() {
+    let mut optional = Some(0);
+
+    while let Some(i) = optional {
+        if i > 9 {
+            println!("Greater than 9, quit!");
+            optional = None;
+        } else {
+            println!("`i` is `{:?}`. Try again.", i);
+            optional = Some(i + 1);
+        }
+    }
+}

rustbyexample/fn.d/closures.d/anonymity.rs

@@ -0,0 +1,14 @@
+fn apply<F>(f: F)
+where
+    F: Fn(),
+{
+    f();
+}
+
+fn main() {
+    let x = 7;
+
+    let print = || println!("{}", x);
+
+    apply(print);
+}

rustbyexample/fn.d/closures.d/capture.rs

@@ -0,0 +1,36 @@
+fn main() {
+    use std::mem;
+
+    let color = String::from("green");
+
+    let print = || println!("`color`: {}", color);
+
+    print();
+
+    let _reborrow = &color;
+    print();
+
+    let _color_moved = color;
+
+    let mut count = 0;
+
+    let mut inc = || {
+        count += 1;
+        println!("`count`: {}", count);
+    };
+
+    inc();
+
+    inc();
+
+    let _count_reborrowed = &mut count;
+
+    let movable = Box::new(3);
+
+    let consume = || {
+        println!("`movable`: {:?}", movable);
+        mem::drop(movable);
+    };
+
+    consume();
+}

rustbyexample/fn.d/closures.d/capture2.rs

@@ -0,0 +1,8 @@
+fn main() {
+    let haystack = vec![1, 2, 3];
+
+    let contains = move |needle| haystack.contains(needle);
+
+    println!("{}", contains(&1));
+    println!("{}", contains(&4));
+}

rustbyexample/fn.d/closures.d/input_parameters.rs

@@ -0,0 +1,36 @@
+fn apply<F>(f: F)
+where
+    F: FnOnce(),
+{
+    f();
+}
+
+fn apply_to_3<F>(f: F) -> i32
+where
+    F: Fn(i32) -> i32,
+{
+    f(3)
+}
+
+fn main() {
+    use std::mem;
+
+    let greeting = "hello";
+    let mut farewell = "goodbye".to_owned();
+
+    let diary = || {
+        println!("I said {}.", greeting);
+
+        farewell.push_str("!!!");
+        println!("Then I screamed {}.", farewell);
+        println!("Now I can sleep. zzzzz");
+
+        mem::drop(farewell);
+    };
+
+    apply(diary);
+
+    let double = |x| 2 * x;
+
+    println!("3 doubled: {}", apply_to_3(double));
+}

rustbyexample/fn.d/closures.rs

@@ -0,0 +1,12 @@
+fn main() {
+    let outer_var = 42;
+
+    let closure_annotated = |i: i32| -> i32 { i + outer_var };
+    let closure_inferred = |i| i + outer_var;
+
+    println!("closure_annotated: {}", closure_annotated(1));
+    println!("closure_inferred: {}", closure_inferred(1));
+
+    let one = || 1;
+    println!("closure returning one: {}", one());
+}

rustbyexample/fn.d/methods.rs

@@ -0,0 +1,74 @@
+struct Point {
+    x: f64,
+    y: f64,
+}
+
+impl Point {
+    fn origin() -> Point {
+        Point { x: 0.0, y: 0.0 }
+    }
+
+    fn new(x: f64, y: f64) -> Point {
+        Point { x: x, y: y }
+    }
+}
+
+struct Rectangle {
+    p1: Point,
+    p2: Point,
+}
+
+impl Rectangle {
+    fn area(&self) -> f64 {
+        let Point { x: x1, y: y1 } = self.p1;
+        let Point { x: x2, y: y2 } = self.p2;
+
+        ((x1 - x2) * (y1 - y2)).abs()
+    }
+
+    fn perimeter(&self) -> f64 {
+        let Point { x: x1, y: y1 } = self.p1;
+        let Point { x: x2, y: y2 } = self.p2;
+
+        2.0 * ((x1 - x2).abs() + (y1 - y2).abs())
+    }
+
+    fn translate(&mut self, x: f64, y: f64) {
+        self.p1.x += x;
+        self.p2.x += x;
+
+        self.p1.y += y;
+        self.p2.y += y;
+    }
+}
+
+struct Pair(Box<i32>, Box<i32>);
+
+impl Pair {
+    fn destroy(self) {
+        let Pair(first, second) = self;
+
+        println!("Destroying Pair({}, {})", first, second);
+    }
+}
+
+fn main() {
+    let rectangle = Rectangle {
+        p1: Point::origin(),
+        p2: Point::new(3.0, 4.0),
+    };
+
+    println!("Rectangle perimeter: {}", rectangle.perimeter());
+    println!("Rectangle area: {}", rectangle.area());
+
+    let mut square = Rectangle {
+        p1: Point::origin(),
+        p2: Point::new(1.0, 1.0),
+    };
+
+    square.translate(1.0, 1.0);
+
+    let pair = Pair(Box::new(1), Box::new(2));
+
+    pair.destroy();
+}

rustbyexample/fn.rs

@@ -0,0 +1,29 @@
+fn main() {
+    fizzbuzz_to(100);
+}
+
+fn is_divisible_by(lhs: u32, rhs: u32) -> bool {
+    if rhs == 0 {
+        return false;
+    }
+
+    lhs % rhs == 0
+}
+
+fn fizzbuzz(n: u32) -> () {
+    if is_divisible_by(n, 15) {
+        println!("fizzbuzz");
+    } else if is_divisible_by(n, 3) {
+        println!("fizz");
+    } else if is_divisible_by(n, 5) {
+        println!("buzz");
+    } else {
+        println!("{}", n);
+    }
+}
+
+fn fizzbuzz_to(n: u32) {
+    for n in 1..=n {
+        fizzbuzz(n);
+    }
+}

rustbyexample/hello.d/print.d/print_debug2.rs

@@ -1,3 +1,4 @@
+#[allow(dead_code)]
 #[derive(Debug)]
 struct Person<'a> {
     name: &'a str,

rustbyexample/hello.d/print.d/print_display.d/testcase_list.rs

@@ -20,6 +20,6 @@ impl fmt::Display for List {
 }
 
 fn main() {
-    let v = List(vec![1, 2, 3]);
+    let v = List(vec![6, 0, 6, 8, 0, 8, 9, 1, 1, 1, 3, 1, 2]);
     println!("{}", v);
 }

rustbyexample/primitives.d/array.rs

@@ -22,5 +22,14 @@ fn main() {
     println!("borrow a section of the array as a slice");
     analyze_slice(&ys[1..4]);
 
-    // println!("{}", xs[5]);
+    let empty_array: [u32; 0] = [];
+    assert_eq!(&empty_array, &[]);
+    assert_eq!(&empty_array, &[][..]);
+
+    for i in 0..xs.len() + 1 {
+        match xs.get(i) {
+            Some(xval) => println!("{}: {}", i, xval),
+            None => println!("Slow down! {} is too far!", i),
+        }
+    }
 }

rustbyexample/primitives.d/literals.rs

@@ -3,6 +3,8 @@ fn main() {
 
     println!("1 - 2 = {}", 1i32 - 2);
 
+    println!("1e4 is {}, -2.5e-3 is {}", 1e4, -2.5e-3);
+
     println!("true AND false is {}", true && false);
     println!("true OR false is {}", true || false);
     println!("NOT true is {}", !true);

rustbyexample/primitives.rs

@@ -1,3 +1,5 @@
+#[allow(unused_variables)]
+#[allow(unused_assignments)]
 fn main() {
     let logical: bool = true;
 

rustbyexample/types.d/alias.rs

@@ -0,0 +1,15 @@
+type NanoSecond = u64;
+type Inch = u64;
+type U64 = u64;
+
+fn main() {
+    let nanoseconds: NanoSecond = 5 as U64;
+    let inches: Inch = 2 as U64;
+
+    println!(
+        "{} nanoseconds + {} inches = {} unit?",
+        nanoseconds,
+        inches,
+        nanoseconds + inches
+    );
+}