22 - 删除排序链表中的重复元素

题目

给定一个排序链表，删除所有重复的元素，使得每个元素只出现一次。

示例 1:

输入: 1->1->2 输出: 1->2

示例 2:

输入: 1->1->2->3->3 输出: 1->2->3

解答

直观解法

看一下next指向的val是不是和当前的相等，相当就指向next的next。

/**
 * Definition for singly-linked list.
 * function ListNode(val) {
 *     this.val = val;
 *     this.next = null;
 * }
 */
/**
 * @param {ListNode} head
 * @return {ListNode}
 */
var deleteDuplicates = function(head) {
    let cur = head
    while(cur && cur.next) {
        if(cur.val === cur.next.val) {
            cur.next = cur.next.next
        } else {
            cur = cur.next
        }
    }
    return head
};

Runtime: 64 ms, faster than 85.11% of JavaScript online submissions forRemove Duplicates from Sorted List.

Memory Usage: 36.1 MB, less than 25.00% of JavaScript online submissions for Remove Duplicates from Sorted List.