关于快速排序的c++算法

#include<iostream>#include<vector>#include<algorithm>using namespace std;class Q_Sort{private:vector<int> buf;protected:int partition(int p,int r);void q_sort(int p, int r);public:Q_Sort(int n);void QuickSort(){ q_sort(0,buf.size()-1);}void Q_Show();};Q_Sort::Q_Sort(int n){for(int i=0;i<n;i++){int m;cin>>m;buf.push_back(m);}}int Q_Sort::partition(int p,int r){int x=buf.at(r);int i=p-1;for(int j=p;j<r;j++){if( buf.at(j)<=x){i++;swap(buf.at(i),buf.at(j));}}swap( buf.at(i+1), buf.at(r));return i+1;}void Q_Sort::q_sort(int p,int r){if( p<r){int q=partition(p,r);Q_Sort::q_sort(p,q-1);Q_Sort::q_sort(q+1,r);}}void Q_Sort::Q_Show(){for( vector<int>::iterator it=buf.begin();it!=buf.end();it++)cout<<*it<<" ";cout<<endl;}int main(){int a=4,b=3;int m;cin>>m;Q_Sort qs(m);//qs.Q_Show();qs.QuickSort();qs.Q_Show();return 0;}