Remove Element

Given an array and a value, remove all instances of that value in place and return the new length.

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

这道题目也是用双指针解决的问题，与Remove Duplicates from Sorted Array 类似，只要保留与value不同的元素就可以了。代码如下：

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