【剑指Offer】36.两个链表的第一个公共结点（Python实现）

题目描述

输入两个链表，找出它们的第一个公共结点。（注意因为传入数据是链表，所以错误测试数据的提示是用其他方式显示的，保证传入数据是正确的）

解法一：栈方法

# -*- coding:utf-8 -*-
# class ListNode:
#     def __init__(self, x):
#         self.val = x
#         self.next = None
class Solution:
    def FindFirstCommonNode(self, pHead1, pHead2):
        # write code here
        stack1 = []
        stack2 = []
        while pHead1:
            stack1.append(pHead1)
            pHead1 = pHead1.next
        while pHead2:
            stack2.append(pHead2)
            pHead2 = pHead2.next
        node1 = None
        while stack1 and stack2 and stack1[-1] is stack2[-1]:
            node1 = stack1.pop()
            stack2.pop()
        return node1