Linked list sorting (?)

leetcode/stuff.py

@@ -1,5 +1,7 @@
 import typing
 
+import stdlib
+
 
 def yep(s: str) -> bool:
     return s.strip().lower().startswith("y")
@@ -158,3 +160,40 @@ class MinStack:
 
     def getMin(self) -> int:  # no qa
         return self._min[-1]
+
+
+def linked_list_to_list(head: stdlib.ListNode | 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.ListNode | None) -> stdlib.ListNode | None:
+    by_val: list[tuple[int, stdlib.ListNode]] = []
+    ret: stdlib.ListNode | None = None
+
+    while head is not None:
+        by_val.append((head.val, head))
+        head = head.next
+
+    cur = ret
+
+    for _, node in sorted(by_val):
+        if cur is None:
+            cur = ret = stdlib.ListNode(node.val)
+            continue
+
+        next_node = stdlib.ListNode(node.val)
+        cur.next = next_node
+        cur = next_node
+
+    return ret