Quick Sort實作[JAVA版]

//*目的:使用者的輸入做Quick_Sort*/

//*安裝版本:J2SE 5.0 以上*/

//*方法一:Scanner*/

import java.util.Scanner;

//*註解為方法二:BufferedReader*/

//import java.io.BufferedReader;

//import java.io.InputStreamReader;

import java.io.IOException;

//*ex.排序方法

public class Quick_Sort{

    //*切割的點也就是取Pivot

    private static int partition(int a[],int left,int right){

         int i,j,temp,pivot;

        i=left+1;

        j=right;

        pivot=a[left];

        do{

            while(a[i]<pivot)i++;

            while(a[j]>pivot)j--;

            if(i<j){

                temp=a[i];

                a[i]=a[j];

                a[j]=temp;

            /* 可以做Bug的找碴~XD

            System.out.print("Begin\n");

            for(int k=0;k<a.length;k++){

                System.out.print(a[k] + " ");

            }

            System.out.print("end\n");

            */

            }

        }while(i<j);

        a[left]=a[j];

        a[j]=pivot;

        return j;

    }

    //*排序方法Quick Sort本體    

    private static void Main_Quick_Sort(int a[],int left,int right){

        int mid;

        if(left<right){

            //*用上個Method找Pivot

            mid = partition(a,left,right);

            //*邊換邊印給你看結果[*依分割次數]

            System.out.print("\n");

            for(int k=0;k<a.length;k++){

                System.out.print(a[k] + " | ");

            }

            System.out.print("\n");

            Main_Quick_Sort(a,left,mid-1);

            Main_Quick_Sort(a,mid+1,right);

        }else{

            //*我搞笑用~XD

            //System.out.print("@");

        }

    }

    //*主執行程式

    public static void main(String args[])throws IOException 

    {

        //*要存的陣列宣告a

        int b[] = new int[10];

        //*讀取輸入值

        //BufferedReader br=

         //    new BufferedReader(new InputStreamReader(System.in));

         Scanner scanner = new Scanner(System.in);

         System.out.print("1.計算輸入10個值的Quick Sort排序~\n"+

                                 "請輸入(都整數喔!!):");    

        for(int k=0;k<b.length;k++){

            b[k] = scanner.nextInt();

        }

        //*做銀幕的Check

        System.out.println("\n2.原本10個整數順序:");    

        for(int k=0;k<b.length;k++){

            System.out.print(b[k] + " | ");

        }

        System.out.println("\n\n3.轉換過程:");

        //**關鍵底枷啦!!要傳陣列給排序方法做

        Main_Quick_Sort(b, 0, b.length-1);

        System.out.println("\n4.排序後10個整數順序:");

        for(int k=0;k<b.length;k++){

            System.out.print(b[k] + " | ");

        }

        //*System.exit(0);

    }

}