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.

Example:

Input: [0,1,0,3,12]
Output: [1,3,12,0,0]

Note:
1.You must do this in-place without making a copy of the array.

2.Minimize the total number of operations.

第一想法是类比冒泡排序写个算法，但是又觉得太繁琐。后来想想，简单点，遇到零就删除，然后再数组末尾添加上就好了，只是对细节上需要做一些处理。具体代码如下。

 

void moveZeroes(vector<int>& nums) {
    int size = nums.size();
    int counter = 0;
    int i = 0;
    while(i+counter<size){
        if (nums[i] == 0) {
            nums.erase(begin(nums) + i);
            nums.push_back(0);
            counter++;
            i = 0;//这一步很重要，需要理解。
        }
        else i++;
    }
}