快速排序

普通快速排序代码如下

#include<iostream>
#include<algorithm>
#include<vector>
#include<set>
using namespace std;
int getindex(vector<int>&arr,int left,int right){
	int m=arr[left];
	while(left<right){
		while(left<right&&arr[right]>=m)
			right--;
		arr[left]=arr[right];

		while(left<right&&arr[left]<=m)
			  left++;

		arr[right]=arr[left];

	}
	arr[left]=m;
    return left;
}
void quicksort(vector<int>&arr,int left,int right){
	if(left<right){
	int mid= getindex(arr,left,right);
	quicksort(arr,left,mid-1);
	quicksort(arr,mid+1,right);
	}
}
int main(){
    vector<int>arr={1,5,3,9,4,56,234,71,3,52,7};
    quicksort(arr,0,arr.size()-1);
    for(int t:arr){
    	cout<<t<<" ";
	}
}