相交链表问题

Posted 2022-02-08 Alice_yufeng

/**
 * Definition for singly-linked list.
 * public class ListNode 
 *     int val;
 *     ListNode next;
 *     ListNode(int x) 
 *         val = x;
 *         next = null;
 *     
 * 
 */
public class Solution 
    public ListNode getIntersectionNode(ListNode headA, ListNode headB) 
        Set<ListNode> visited = new HashSet<ListNode>();
        ListNode temp = headA;
        while (temp != null) 
            visited.add(temp);
            temp = temp.next;
        
        temp = headB;
        while (temp != null) 
            if (visited.contains(temp)) 
                return temp;
            
            temp = temp.next;
        
        return null;