LeetCode算法入门- Remove Element -day20

1. 题目描述
Given an array nums and a value val, remove all instances of that value in-place 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.

The order of elements can be changed. It doesn’t matter what you leave beyond the new length.

Example 1:

Given nums = [3,2,2,3], val = 3,

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

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

Example 2:

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

Your function should return length = 5, with the first five elements of nums containing 0, 1, 3, 0, and 4.

Note that the order of those five elements can be arbitrary.

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

2. 题目分析：
   这里题目的意思是指返回一个数组，数组里面只有值不等于target的元素，最后返回数组的长度

3. Java实现

class Solution {public int removeElement(int[] nums , int val) {int index = -1;int len = nums.length;for(int i = 0; i < len; i++){if(nums[i] != val){nums[++index] = nums[i];}}return index  + 1;}
}