876. Middle of the Linked List - LeetCode

Posted 2020-12-27 okokabcd

Question

876.?Middle of the Linked List

Solution

题目大意：求链表的中间节点

思路：构造两个节点，遍历链接，一个每次走一步，另一个每次走两步，一个遍历完链表，另一个恰好在中间

Java实现：

public ListNode middleNode(ListNode head) {
    ListNode slow = head;
    ListNode fast = head;
    while (fast != null) {
        fast = fast.next;
        if(fast != null) {
            fast = fast.next;
            slow = slow.next;
        }
    }
    return slow;
}