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1：

class Solution {public:    void moveZeroes(vector<int>& nums) {        int zero=0;        while(zero<nums.size()&&nums[zero]!=0)            zero++;        int nonzero = zero+1;        while(nonzero<nums.size()&&nums[nonzero]==0)            nonzero++;        while(nonzero<nums.size()){            if(nums[nonzero]==0)                nonzero++;            else                swap(nums[nonzero++],nums[zero++]);        }    }};

方法2：同方法1一样，但是代码更加简洁。

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