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java实现冒泡排序以及二分法查找

import java.util.Scanner;

public class SortAndFind {
    boolean HalveFin(int right,int left,int array[],int num)//二分查找
    {
        int mid;
        while (right <= left)
        {
            mid = (right + left)/2;
            if(array[mid] > num)
            {
                left = mid-1;
            }else if(array[mid] < num)
            {
                right = mid+1;
            }else
            {
                System.out.println("num已找到");
                return true;
            }
        }
        return false;
    }

    static void swap(int array[],int i,int j)//交换两个数
    {
        int temp;
        temp = array[i];
        array[i] = array[j];
        array[j] = temp;

    }

    void SoakSort(int array[])//冒泡排序
    {
        int flag;
        for(int i = 0; i < array.length-1; i++)
        {
            flag = 0;
            for (int j = 0; j < array.length-1-i; j++)
            {
                if(array[j] > array[j+1])
                {
                swap(array,j,j+1);
                flag = 1;
                }
            }
            if(flag == 0)//flag用来判断如果在一趟冒泡排序后没有任何数交换，说明顺序已经排好，直接结束所有循环。
            {
                System.out.println("冒泡排序结束");
                break;
            }
        }
    }
 public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        System.out.println("请输入数组长度:");
        int n = scan.nextInt();
        SortAndFind sortAndFind = new SortAndFind();
        int[] array=new int[n];
        System.out.println("请输入数组array的"+n+"个值");
        for (int i = 0 ; i < array.length ;i++)//数组输入
        {
            array[i] = scan.nextInt();
        }
        System.out.println("即将进行冒泡排序……");
        sortAndFind.SoakSort(array);//冒泡排序
        for (int i:array)
        {
            System.out.print(i+">");
        }
        System.out.println();
        System.out.println("请输入需要从数组array中查找的数num:");
        int num = scan.nextInt();
        System.out.println("即将进行二分法查找");
        boolean bool = sortAndFind.HalveFin(0,array.length-1,array,num);//二分法查找
        if(bool)
        {
            System.out.println("数组才采用二分法已查找到num");
        }else
            System.out.println("数组中没有num");
  }
}