Update 92-reverse-linked-list-ii.js

Author: everthis

92-reverse-linked-list-ii.js

@@ -84,6 +84,40 @@ const reverseBetween = function(head, m, n) {
     return dummy.next;
 };
 
+// another
+
+/**
+ * Definition for singly-linked list.
+ * function ListNode(val, next) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.next = (next===undefined ? null : next)
+ * }
+ */
+/**
+ * @param {ListNode} head
+ * @param {number} left
+ * @param {number} right
+ * @return {ListNode}
+ */
+const reverseBetween = function(head, left, right) {
+  if(head == null || left === right) return head
+  const dummy = new ListNode()
+  dummy.next = head
+  let tail = null, p = dummy
+  for(let i = 1; i < left; i++) {
+    p = p.next
+  } 
+  tail = p.next
+  let tmp
+  for(let i = 0; i < right - left; i++) {
+    tmp = p.next
+    p.next = tail.next
+    tail.next = tail.next.next
+    p.next.next = tmp
+  }
+
+  return dummy.next
+};
 
 // another