第六周作业

1.定义长度为5的整型数组,输入他们的值,用冒泡排序后输出.

package book1;

public class asd {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int[] a = {2,6,3,5,1,4};
        for (int i = 0; i < a.length-1; i++) {
            for (int j = 0; j < a.length-1-i; j++) {
                if(a[j]>a[j+1]){
                    int b = a[j];
                    a[j] = a[j+1];
                    a[j+1] = b;
                }
                
            }
            
        }
        for (int i = 0; i < a.length; i++) {
            System.out.print(a[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 book1;

import java.util.*;

public class asd {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner input = new Scanner(System.in);
        System.out.println("请输入一个数");
        int a = input.nextInt();
        boolean flag = false;
        int[] b = { 34, 22, 35, 67, 45, 66, 12, 33 };
        int c = 0;
        for (int i = 0; i < b.length; i++) {
            if (b[i] == a) {
                c = i;
                System.out.println("下标为" + c);
                flag = true;
            }
        }
        if (flag == false) {
            System.out.println("no 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 book1;

public class asd {

    public static void main(String[] args) {
        double[][] arr = { { 11, 12, 13, 14 }, { 15, 16, 17, 18 }, { 19, 20, 11, 12 }, { 13, 14, 15, 16 }, { 17, 18, 19, 20 } };
        for (int i = 0; i < arr.length; i++) {
            System.out.println();
            for (int j = 0; j < arr[i].length; j++) {
                System.out.print(arr[i][j] + "  ");
            }
        }
    }

}

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 book1;

public class asd {

    public static void main(String[] args) {
        int[][] a = { { 1, 2, 3, 4 }, { 5, 6, 7, 8 }, { 9, 10, 11, 12 } };
        int max = a[0][0];
        for (int i = 0; i < a.length; i++) {
            for (int j = 0; j < a[i].length; j++) {
                if (a[i][j] > max) {
                    max = a[i][j];
                }
            }
        }
        System.out.println("最大值为" + max);
    }
}