Javascript(leetcode#83) Remove Duplicates from Sorted List

Difficult:Easy

題目

Given the head of a sorted linked list, delete all duplicates such that each element appears only once. Return the linked list sorted as well.

翻譯

給定排序鍊錶的頭部，刪除所有重複項，使每個元素只出現一次。返回排序好的鍊錶。

範例

Example 1:

Input: head = [1,1,2]
Output: [1,2]

Example 2:

Input: head = [1,1,2,3,3]
Output: [1,2,3]

解題思路

1.設當前及存放開頭的變數
2.當遇到相同值時，依序往前比較

Solution

var deleteDuplicates = function (head) {
    let cur = head;
    let headnode = head;
    while (cur != null&&cur.next!=null) {
        let curval = cur.val;
        if (curval == cur.next.val) {
            let next = cur.next;
            while (next != null && next.val == curval) {
                next = next.next;
            }
            cur.next=next;
            cur=next;
        }else{
            cur=cur.next;
        }
    }
    return headnode;
};