Java第五次作业

1.定义长度位5的整型数组,输入他们的值,用冒泡排序后输出.
package demo3;

import java.util.Scanner;

public class day01 {

    public static void main(String[] args) {
        int[] arr={32,12,94,73,21};
        for (int x = 0; x < arr.length; x++) {
            for (int y = 0; y < arr.length-x-1; y++) {
                if (arr[y]>arr[y+1])
                {
                    int temp=arr[y];
                    arr[y]=arr[y+1];
                    arr[y+1]=temp;
                }
            }
        }
        for (int i= 0; i< arr.length; i++) {
            System.out.print(arr[i]+"	");
        }
      
      }

}

2.定义数组{34,22,35,67,45,66,12,33},输入一个数a,查找在数组中是否存在,如果存在,输出下标,不存在输出"not found"
package demo3;

import java.util.Scanner;

public class day01 {

    public static void main(String[] args) {
        int[] arr={34,22,35,67,45,66,12,33};
        Scanner input=new Scanner(System.in);
        System.out.print("请输入一个数a：");
        int a=input.nextInt();
        for (int x = 0; x < arr.length; x++) {
            if (a==arr[x])
                {
                    System.out.println("下标为"+x);
                    break;
                }
            else{
                System.out.println("not found");
            }
            }
      }

    }

3.以矩阵的形式输出一个double型二维数组（长度分别为5、4，值自己设定）的值。
package demo3;

import java.util.Scanner;

public class day01 {

    public static void main(String[] args) {
        double[][] arr={{3.4,2.2,3.5,6.7},{4.5,6.6,1.2,3.3},{2.1,4,3,9.1},{1,2,23,1},{2,3,4,3}};
        for (int x = 0; x < 5; x++) {
            for (int i = 0; i < 4; i++) {
                System.out.print(arr[x][i]+"	");
            }
            System.out.println();
        }
    }
 }

4.定义一个二维数组(长度分别为3,4,值自己设定),求该二维数组的最大值.
package demo3;
public class day01
{
    public static void main(String[] args) 
{
        int arr[][]={{10,2,30},{43,52,26},
                {77,18,39},{10,1,42}};
        int max=arr[0][0];
        for(int i=0;i<arr.length;i++){
            for(int j=0;j<arr[i].length;j++){
                if(arr[i][j]>max){
                    max=arr[i][j];
                }
            }
        }
        System.out.println("数组的最大值为"+max);
   }
}