题解 | #删除有序链表中重复的元素-I#

import java.util.*;

/*
 * public class ListNode {
 *   int val;
 *   ListNode next = null;
 *   public ListNode(int val) {
 *     this.val = val;
 *   }
 * }
 */

public class Solution {
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     * 
     * @param head ListNode类 
     * @return ListNode类
     */
    public ListNode deleteDuplicates (ListNode head) {
        // write code here
        if (head == null) return null;
        ListNode fast = head.next;
        ListNode slow = head;
        while(fast != null) {
            while(fast != null && fast.val == slow.val) fast = fast.next;
            slow.next = fast;
            slow = slow.next;
            if (fast != null) fast = fast.next;
        }
        return head;
    }
}

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