leetcode: Remove Element

问题描述：

Given an array and a value, 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 in place with constant memory.

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

Example:
Given input array nums = [3,2,2,3], val = 3

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

原问题链接：https://leetcode.com/problems/remove-element/

 

问题分析

　　这个问题需要的是移除给定数组里一个特定的值。和前一个问题类似，用两个数值一个表示当前遍历到的索引，一个用来记录保存当前合法值的索引。具体的实现如下：

 

public class Solution {
    public int removeElement(int[] nums, int val) {
        if(nums == null || nums.length == 0) return 0;
        int i, j = 0;
        for(i = 0, j = 0; i < nums.length; i++) {
            if(nums[i] != val) nums[j++] = nums[i];
        }
        return j;
    }
}