leetcode: finished #143

content/leetcode/2024/2.md

@@ -3,6 +3,49 @@ title: 2024.2
 draft: false
 ---
 
+# 2024.2.22
+
+```typescript
+/*
+ * @lc app=leetcode.cn id=143 lang=typescript
+ *
+ * [143] 重排链表
+ */
+
+class ListNode {
+  val: number;
+  next: ListNode | null;
+  constructor(val?: number, next?: ListNode | null) {
+    this.val = val === undefined ? 0 : val;
+    this.next = next === undefined ? null : next;
+  }
+}
+
+// @lc code=start
+function reorderList(head: ListNode | null): void {
+  if (head === null) return;
+
+  const list: ListNode[] = [];
+  while (head !== null) {
+    list.push(head);
+    head = head.next;
+  }
+
+  for (let i = 0, j = list.length - 1; i < j; i++, j--) {
+    list[i].next = list[j];
+    if (i + 1 < j - 1) {
+      list[j].next = list[i + 1];
+    } else if (i + 1 === j - 1) {
+      list[j].next = list[i + 1];
+      list[i + 1].next = null;
+    } else if (i + 1 === j) {
+      list[j].next = null;
+    }
+  }
+}
+// @lc code=end
+```
+
 # 2024.2.21
 
 ```python