https://leetcode.cn/problems/move-zeroes/description/?envType=study-plan-v2&envId=top-100-liked
####关注点不要只放在0上面，要放在非零元素

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

    }
};