[148] 排序链表

src/leecode/javascript/148.排序链表.js

@@ -0,0 +1,48 @@
+/*
+ * @lc app=leetcode.cn id=148 lang=javascript
+ *
+ * [148] 排序链表
+ */
+
+// @lc code=start
+/**
+ * Definition for singly-linked list.
+ * function ListNode(val, next) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.next = (next===undefined ? null : next)
+ * }
+ */
+/**
+ * @param {ListNode} head
+ * @return {ListNode}
+ */
+var sortList = function (head) {
+  if (!head || !head.next) {
+    return head;
+  }
+  let slow = head,
+    fast = head.next;
+  while (fast && fast.next) {
+    slow = slow.next;
+    fast = fast.next.next;
+  }
+  const tmp = slow.next;
+  slow.next = null;
+  let left = sortList(head);
+  let right = sortList(tmp);
+  let h = new ListNode(0);
+  const ret = h;
+  while (left && right) {
+    if (left.val < right.val) {
+      h.next = left;
+      left = left.next;
+    } else {
+      h.next = right;
+      right = right.next;
+    }
+    h = h.next;
+  }
+  h.next = left == null ? right : left;
+  return ret.next;
+};
+// @lc code=end