剑指Offer 52 两个链表的第一个公共节点

两个链表的第一个公共节点

输入两个链表，找出它们的第一个公共结点。

# -*- coding:utf-8 -*-
# class ListNode:
#     def __init__(self, x):
#         self.val = x
#         self.next = None
class Solution:
    def FindFirstCommonNode(self, pHead1, pHead2):
        l1 = pHead1
        l2 = pHead2
        while l1 != l2:
            l1 = pHead2 if l1 == None else l1.next
            l2 = pHead1 if l2 == None else l2.next
        return l1
        # write code here

 

Java版代码，leetcode地址：

public class Solution {
    public ListNode getIntersectionNode(ListNode headA, ListNode headB) {
        ListNode l1 = headA;
        ListNode l2 = headB;
        while (l1 != l2) {
            if (l1 == null) {
                l1 = headA;
            } else {
                l1 = l1.next;
            }

            if (l2 == null) {
                l2 = headB;
            } else {
                l2 = l2.next;
            }
        }
        return l1;
    }
}