Cloned undirected graph

leetcode/stuff.py

@@ -1,6 +1,5 @@
+import collections.abc
 import copy
-import itertools
-import math
 import random
 import typing
 
@@ -581,3 +580,48 @@ def accum_sub_array_maxes(nums: list[int]) -> list[int]:
         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)