快速排序代码Java

import java.util.Arrays;
import java.util.PriorityQueue;
import java.util.Queue;
import java.util.Scanner;


public class Main {
    private static int mod = (int) 1e9+7;
    private static final int N = 100010;
    private static int[] q = new int[N];


    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();

        for(int i = 0; i < n; i++){
            q[i] = sc.nextInt();
        }

        quickSort(q, 0, n -1);

        for(int i = 0; i < n; i++){
            System.out.print(q[i] + " ");
        }


    }
    public static void quickSort(int[] q, int l ,int r){
        if(l >= r)return;
        int i = l - 1, j = r + 1, x = q[l + r >> 1];
        while(i < j){
            while(q[++i] < x);
            while(q[--j] > x);
            if(i < j){
                int t = q[i];
                q[i] = q[j];
                q[j] = t;
            }
        }
        quickSort(q, l, j);
        quickSort(q,j + 1, r);
    }
}

找中间的值，小于的放左边，大于的放右边，递归