快速排序算法JAVA实现

 

package org.test3;

public class Test3 {
    public static void main(String args[]){
        new Test3();
    }
    public Test3(){
        int[] arrays = { 10, 32, 22, 37, 2, 5, 23, 11, 21, 15, 18, 3, 26 };
        System.out.println("进行快速排序之前的为");
        for(int x:arrays){
            System.out.print(x + " ");
        }
        quickSort(arrays,0,arrays.length-1);
        System.out.println("\n进行快速排序之后的为");
        for(int x:arrays){
            System.out.print(x + " ");
        }
    }
    /**
     * 进行快排
     * @param arrays
     * @param low
     * @param high
     */
    private void quickSort(int[] arrays,int low ,int high){
        int i = low;
        int j = high;
        if(i<j){
            int key = arrays[i];
            while(i<j){
                while(i<j&&arrays[j]>key){
                    j--;
                }
                if(i<j){
                    arrays[i] = arrays[j];
                    i++;
                }
                while(i<j&&arrays[i]<key){
                    i++;
                }
                if(i<j){
                    arrays[j] = arrays[i];
                    j--;
                }
            }
            arrays[i] = key;
            quickSort(arrays,low,i-1);  //继续前半截的排序
            quickSort(arrays,i+1,high); //继续后半截的排序
        }
    }
}