排序算法-快速排序

package com.ifreewolf.test.sort;

/**
 * @author fgs
 * @since 2020/10/11 11:32
 */
public class QuickSort {
    static final int SIZE = 18;
    public static void quickSort(int[] arr, int left, int right){
        int f, t;
        int rtemp, ltemp;
        ltemp = left;
        rtemp = right;
        f = arr[(left + right) / 2];
        while (ltemp < rtemp){
            while (arr[ltemp] < f){
                ++ltemp;
            }
            while (arr[rtemp] > f){
                --rtemp;
            }
            if(ltemp <= rtemp){
                t = arr[ltemp];
                arr[ltemp] = arr[rtemp];
                arr[rtemp] = t;
                --rtemp;
                ++ltemp;
            }
        }
        if(ltemp == rtemp){
            ltemp++;
        }
        if (left < rtemp){
            quickSort(arr, left, ltemp - 1);
        }
        if (ltemp < right){
            quickSort(arr, rtemp + 1, right);
        }
    }

    public static void main(String[] args) {
        int[] shuzu = new int[SIZE];
        int i;

        for (i = 0; i < SIZE; ++i){
            shuzu[i] = (int)(100 + Math.random()*101);
        }

        System.out.println("排序前的数组为：");
        for (int j = 0; j < SIZE; j++) {
            System.out.print(shuzu[j] + " ");
        }
        System.out.println();

        quickSort(shuzu, 0, SIZE - 1);
        System.out.println("排序后的数组:");
        for (int j = 0; j < SIZE; j++) {
            System.out.print(shuzu[j] + " ");
        }
        System.out.println();
    }
}