题解 | #两个链表的第一个公共结点#

# class ListNode:
#     def __init__(self, x):
#         self.val = x
#         self.next = None

#
# 
# @param pHead1 ListNode类 
# @param pHead2 ListNode类 
# @return ListNode类
#
class Solution:
    def FindFirstCommonNode(self , pHead1 , pHead2 ):
        # write code here
        # 先遍历其中一个数组，再遍历另外一个数组
		# 当找到第一个相等的节点，就记录为start，
		# 假如一直遍历到结束都是相等的，则说明有重复节点，返回start，否则返回空
        value=[]
        h1 = pHead1
        while h1 is not None:
            value.append(h1.val)
            h1 = h1.next
        h2 = pHead2
        while h2 is not None:
            if h2.val in value:
                start = h2
                i = value.index(h2.val) # 节点的值按理说应该是不重复的，否则无从判断是否有共有的值
                h2 = h2.next
                while h2 is not None:
                    if h2.val == value[i+1]:
                        i += 1
                        h2 = h2.next
                    else:
                        break
                if i >= len(value) - 1:
                    return start
            else: 
                h2 = h2.next
        return None