快速排序

#include<iostream>#include<iterator>#include<vector>#include<algorithm>#include<time.h>using namespace std;/**快速排序问题*/void Fast_sort(vector<int>& a,int beg,int end){if(beg+1>=end) return;int key = beg;for (int i = beg , j = end; i < j; ){if(key == i){do{j--;} while (a[j]>a[key]);key = j;}else{do{i++;} while (a[i]<a[key]);key = i;}swap(a[i],a[j]);}Fast_sort(a,beg,key);Fast_sort(a,key+1,end);}int main(){long start, end;vector<int> vec;copy(istream_iterator<int>(cin),istream_iterator<int>(),back_inserter(vec));start = clock();Fast_sort(vec,0,vec.size());end = clock();copy(vec.begin(),vec.end(),ostream_iterator<int>(cout," "));cout<<endl;cout <<"程序运行时间（单位：毫秒）： "<< end-start <<endl;}