【Java】快速排序

import java.util.Arrays;

public class QuickSort {
    public static void sort(int[] a, int low, int high) {
        int i, j;
        int index;
        if (low > high) {
            return;
        }
        i = low;
        j = high;
        index = a[i];
        while (i < j) {
            while (i < j && a[j] >= index) {
                j--;
            }
            if (i < j) {
                a[i++] = a[j];
            }
            while (i < j && a[i] < index) {
                i++;
            }
            if (i < j) {
                a[j--] = a[i];
            }
        }
        a[i] = index;
        sort(a, low, i - 1);
        sort(a, i + 1, high);
    }

    public static void quickSort(int[] a) {
        sort(a, 0, a.length - 1);
    }

    public static void main(String[] args) {
        int[] a = {5, 4, 9, 8, 6, 0, 1, 3, 2};
        quickSort(a);
        System.out.println(Arrays.toString(a));
    }
}