283. Move Zeroes

Given an array nums, write a function to move all 0’s to the end of it while maintaining the relative order of the non-zero elements.

For example, given nums = [0, 1, 0, 3, 12], after calling your function, nums should be [1, 3, 12, 0, 0].

Note:
You must do this in-place without making a copy of the array.
Minimize the total number of operations.

方法很巧妙。

class Solution {public:    void moveZeroes(vector<int>& nums) {        int idx = 0;        int len = nums.size();        for(int i = 0; i < len; i++)        {            if(nums[i] != 0)            {                nums[idx++] = nums[i];            }        }        for(int i = idx; i < len; i++)        {            nums[i] = 0;        }    }};