27. Remove Element

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.

给定一个数组和一个值，删除该值的所有实例，并返回新的长度。 元素的顺序可以被改变，也不关心最终的数组长度。

    public int removeElement(int[] nums, int val) {
        if (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;  
    }