LeetCode题解-相交链表-Java

不多说，上代码，一看就懂。主要思路就是 从链表尾往链表头看

public class Solution {
   
    public ListNode getIntersectionNode(ListNode headA, ListNode headB) {
   
        int countA=getCount(headA);
        int countB=getCount(headB);
        int gap=Math.abs(countA-countB);
        if (countA>countB){
   
            while (gap>0){
   
                headA=headA.next;
                gap--;
            }
        }else{
   
            while (gap>0){
   
                headB=headB.next;
                gap--;
            }
        }
        return getResult(headA,headB);
    }
    public int getCount(ListNode node){
   
        int count=0;
        while (node!=null){
   
            count++;
            node=node.next;
        }
        return count;
    }
    public ListNode getResult(ListNode nodeA,ListNode nodeB){
   
        while (nodeA!=null){
   
            if (nodeA==nodeB){
   
                return nodeA;
            }
            nodeA=nodeA.next;
            nodeB=nodeB.next;
        }
        return null;
    }
}