快排Java模板

Posted 2021-03-07 INnoVation-V2

import java.util.Scanner;
import java.io.BufferedInputStream;
public class Main{
    public static void quickSort(int[] q,int l,int r){
        if(l>=r) return;
        int x=q[(l+r)>>1],i=l-1,j=r+1;
        while(i<j){
            do ++i; while(q[i]<x);
            do --j; while(q[j]>x);
            if(i<j){
                int temp=q[i];
                q[i]=q[j];
                q[j]=temp;
            }
        }
        quickSort(q,l,j);
        quickSort(q,j+1,r);
    }
    public static void main(String[] args){
        Scanner sc=new Scanner(new BufferedInputStream(System.in));
        int len=sc.nextInt();
        int[] q=new int[len];
        for(int x=0;x<len;++x){
            q[x]=sc.nextInt();
        }
        quickSort(q,0,len-1);
        for(int x:q){
            System.out.print(x+" ");
        }
    }
}