Move Zeroes

题目：

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:

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

解析：

自己写的代码

class Solution {
public:
    void moveZeroes(vector<int>& nums) {
        vector<int>::size_type i;
        for(i=0;i < nums.size();i++)
        {
            vector<int>::iterator it = find(nums.begin(),nums.end()-i,0);
            if(it == nums.end()-i)
                break;
            else
            {
                nums.erase(it);
                nums.push_back(0);
            }
        }
    }
};

最然通过了，但是时间长，感觉想法也比较笨，事实上通过一次遍历即可

class Solution {
public:
    void moveZeroes(vector<int>& nums) {
        int n = nums.size();
        int left = 0, right = 0;
        while (right < n){
            if (nums[right]){
                nums[left] = nums[right];
                left++;
            }
            right++;
        }
        while (left < n)
            nums[left++] = 0;
    }
};