From a8d82b180a48ea9f8d4c2336be21dbf6167a6ec8 Mon Sep 17 00:00:00 2001
From: Dan Buch <dan@meatballhat.com>
Date: Sat, 21 Oct 2023 08:41:41 -0400
Subject: [PATCH] Sorting linked list with mutation (oh no)

---
 leetcode/stuff.py      | 12 +++++-----
 leetcode/test_stuff.py | 50 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 57 insertions(+), 5 deletions(-)

diff --git a/leetcode/stuff.py b/leetcode/stuff.py
index 6c1f3ea..29096a4 100644
--- a/leetcode/stuff.py
+++ b/leetcode/stuff.py
@@ -187,13 +187,15 @@ def sort_linked_list(head: stdlib.ListNode | None) -> stdlib.ListNode | None:
 
     cur = ret
 
-    for _, node in sorted(by_val):
+    for _, node in sorted(by_val, key=lambda v: v[0]):
         if cur is None:
-            cur = ret = stdlib.ListNode(node.val)
+            cur = ret = node
             continue
 
-        next_node = stdlib.ListNode(node.val)
-        cur.next = next_node
-        cur = next_node
+        cur.next = node
+        cur = cur.next
+
+    if cur is not None:
+        cur.next = None
 
     return ret
diff --git a/leetcode/test_stuff.py b/leetcode/test_stuff.py
index bf26267..941392b 100644
--- a/leetcode/test_stuff.py
+++ b/leetcode/test_stuff.py
@@ -92,6 +92,56 @@ def test_min_stack(ops: list[tuple[str] | tuple[str, int]], expected: list[int |
                 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.ListNode | None, expected: stdlib.ListNode | None):