Merge pull request youngyangyang04#926 from Jerry-306/patch-46

更正 0019 删除链表中倒数第N个节点 JavaScript 代码

Author: youngyangyang04

problems/0019.删除链表的倒数第N个节点.md

@@ -173,8 +173,7 @@ var removeNthFromEnd = function(head, n) {
     let ret = new ListNode(0, head),
         slow = fast = ret;
     while(n--) fast = fast.next;
-    if(!fast) return ret.next;
-    while (fast.next) {
+    while (fast.next !== null) {
         fast = fast.next; 
         slow = slow.next
     };