博客

import java.text.SimpleDateFormat;
import java.util.Date;

public class QuickSort {

    public static void main(String[] args) {
        int[] array = new int[100000000];
        for (int i = 0; i < 100000000; i++) {
            array[i] = (int) (Math.random() * 2140000000);
        }
        Date startDate = new Date();
        SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        System.out.println("start   :" + simpleDateFormat.format(startDate));
        quickSort(array, 0, array.length - 1);
        Date endDate = new Date();
        System.out.println("end     :" + simpleDateFormat.format(endDate));
    }

    public static void quickSort(int[] array, int left, int right) {
        int l = left;
        int r = right;
        int pivot = array[(left + right) / 2];
        while (l < r) {
            while (array[l] < pivot) {
                l++;
            }
            while (array[r] > pivot) {
                r--;
            }
            if (l >= r) {
                break;
            }
            array[l] = array[l] + array[r] - (array[r] = array[l]);
            if (array[l] == pivot) {
                r--;
            }
            if (array[r] == pivot) {
                l++;
            }
        }
        if (l == r) {
            l++;
            r--;
        }
        if (left < r) {
            quickSort(array, left, r);
        }
        if (right > l) {
            quickSort(array, l, right);
        }
    }
}