LeetCode 26 Remove Duplicates from Sorted Array

题目:

Given a sorted array nums, remove the duplicates in-place such that each element appear only once and return the new length.

Do not allocate extra space for another array, you must do this by modifying the input array in-place with O(1) extra memory.

Example 1:

Given nums = [1,1,2],

Your function should return length = 2, with the first two elements of nums being 1 and 2 respectively.

It doesn't matter what you leave beyond the returned length.

Example 2:

Given nums = [0,0,1,1,1,2,2,3,3,4],

Your function should return length = 5, with the first five elements of nums being modified to 0, 1, 2, 3, and 4 respectively.

It doesn't matter what values are set beyond the returned length.

解答:

移除数组中的重复元素,题目中的基本要求为原地执行,即在原有数组上操作,只需一个下标用于遍历(i),一个用于指示不重复元素的现有位置(k)即可,这是一个实用小技巧,在后面几道简单题中也可以用到。

class Solution {
    public int removeDuplicates(int[] nums) {
        int k=0;
        
        for(int i=1;i<nums.length;i++)
        {
            if(nums[i]!=nums[k])
            {
                nums[++k] = nums[i];
            }
        }
        
        return k+1;
    }
}

 

posted @ 2020-03-19 17:13  好麻烦快点  阅读(117)  评论(0编辑  收藏  举报