题解 | #链表中环的入口结点#
链表中环的入口结点
http://www.nowcoder.com/practice/253d2c59ec3e4bc68da16833f79a38e4
遍历链表,将每个节点存放到一个list中,如果当前节点在list中存在,则返回当前节点,如果不存在,则继续查找下一个节点
/*
public class ListNode {
int val;
ListNode next = null;
ListNode(int val) {
this.val = val;
}
}
*/
import java.util.*;
public class Solution {
public ListNode EntryNodeOfLoop(ListNode pHead) {
List<ListNode> listNodes = new LinkedList<>();
while (pHead != null) {
if (listNodes.contains(pHead)) {
return pHead;
} else {
listNodes.add(pHead);
pHead = pHead.next;
}
}
return null;
}
}