判断链表是否成环
题目描述
判断一个链表是否有环
代码
js
// leetcode 原题： 141.linked-list-cycle
var hasCycle = function(head) {
if (head === null) return false;
if (head.next === null) return false;
let fast = head.next;
let slow = head;
while (fast && fast.next) {
if (fast === slow) return true;
slow = slow.next;
const next = fast.next;
fast = next && next.next;
}
return false;
};// leetcode 原题： 141.linked-list-cycle
var hasCycle = function(head) {
if (head === null) return false;
if (head.next === null) return false;
let fast = head.next;
let slow = head;
while (fast && fast.next) {
if (fast === slow) return true;
slow = slow.next;
const next = fast.next;
fast = next && next.next;
}
return false;
};