面向对象第七次上机作业

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 three;
import java.util.Scanner;
public class text1 {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int[] arr=new int[5];
        Scanner input=new Scanner(System.in);
        for(int a=0;a<arr.length;a++){
        System.out.println("请输入第"+(a+1)+"个数");
        arr[a] = input.nextInt();    
        }
        for(int i=0;i<arr.length-1;i++){
            for(int j=0;j<arr.length-1-i;j++){
                if (arr[j]>arr[j+1]){
                    int temp=arr[j];
                    arr[j]=arr[j+1];
                    arr[j+1]=temp;
                }
            }
        }
        for(int i=0;i<arr.length;i++){
            System.out.println(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 three;
import java.util.Scanner;
public class text2 {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int[] arr={34,22,35,67,45,66,12,33};
        Scanner input=new Scanner(System.in);
        boolean flag= false;
        System.out.println("请输入一个数：");
        int a=input.nextInt();
         for (int i = 0; i < arr.length; i++) {
                if (arr[i] == a) {
                    System.out.println("该数的下标是：" + i);
                    flag = true;
                }
            }
                if(flag == false){
                    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 three;

public class text3 {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        double[][] arr = { { 1, 2, 3, 4, 5 }, { 6, 7, 8, 9, 10 }, { 11, 12, 13, 14, 15 }, { 16, 17, 18, 19, 20 } };
        for (int i = 0; i < arr.length; i++){
            for (int j = 0; j < arr[i].length; j++) {

                System.out.print(arr[i][j] + " \t");

            }
            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 three;

public class text4 {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int[][] arr={{25,28,26,55},
                {25,63,88,78},
                {99,25,36,56}};
        int max=arr[0][0];
        for(int i=0;i<arr.length;i++){
            for(int j=0;j<arr[i].length;j++){
                if(max<arr[i][j]){
                    max=arr[i][j];
                }
            }
        }
        System.out.println("次二维数组的最大值是："+max); 
        
    }
}