题解 | 两个链表的第一个公共结点

/*
struct ListNode {
	int val;
	struct ListNode *next;
	ListNode(int x) :
			val(x), next(NULL) {
	}
};*/
class Solution {
public:
    ListNode* FindFirstCommonNode( ListNode* pHead1, ListNode* pHead2) {
		ListNode* vh1 = pHead1;
		ListNode* vh2 = pHead2;
		int l1 = 0;
		int l2 = 0;
		while(vh1){
			l1++;
			vh1=vh1->next;
		}
		while(vh2){
			l2++;
			vh2=vh2->next;
		}
		vh1 = pHead1;
		vh2 = pHead2;
		if(l1 > l2){
			for(int i = 0 ; i < l1- l2;i ++){
				vh1 = vh1->next;
			}
		}
		else{
			for(int i = 0 ; i < l2 - l1 ; i ++){
				vh2 = vh2->next;
			}
		}
		while(vh2!=vh1){
			vh2 = vh2->next;
			vh1 = vh1->next;
		}
		return vh1;
        
    }
};