全排列算法c++实现

问题：

Given a collection of numbers, return all possible permutations.For example,[1,2,3] have the following permutations:[1,2,3], [1,3,2], [2,1,3], [2,3,1], [3,1,2], and [3,2,1].

Solution:

#include <iostream>#include<vector>#include<algorithm>using namespace std;class Solution {public:    vector<vector<int> > permute(vector<int> &num)    {        vector<vector<int> > resultVector;        sort(num.begin(),num.end());//STL algorithm funtion        do        {            vector<int> vOne;            for(int i=0;i<num.size();i++)                vOne.push_back(num[i]);            resultVector.push_back(vOne);        }while(next_permutation(num.begin(),num.end()));//next_permutation you can find in STL        return resultVector;    }    vector<vector<int> > permuteOrder(int n)    {        vector<int> num;        for(int i=1;i<=n;i++)            num.push_back(i);        return permute(num);    }    void printCollection(vector<vector<int> > &vResult)    {        for(vector<vector<int> >::const_iterator iter = vResult.begin();iter!=vResult.end();iter++)        {            for(vector<int>::const_iterator it = (*iter).begin();it!=(*iter).end();it++)            {                cout<<*it<<" ";            }            cout<<endl;        }    }};int main(){    vector<int> num ;    num.push_back(1);    num.push_back(3);    num.push_back(2);    Solution so;    cout<<"permutation"<<endl;    vector<vector<int> >  vResult = so.permute(num);    so.printCollection(vResult);    cout<<"order permutation"<<endl;    vector<vector<int> >  vOrderResult = so.permuteOrder(3);    so.printCollection(vOrderResult);        return 0;}