第六周作业

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 chap1;

import java.util.Scanner;

public class Main
{
    public static void main(String[] args)
    {
        int[] a = new int[5];
        Scanner s = new Scanner(System.in);
        for (int i = 1; i <= 5; i++)
        {
            System.out.println("请输入第" + i + "个值");
            a[i - 1] = s.nextInt();
        }
        for (int i = 0; i < a.length - 1; i++)
        {
            for (int j = 0; j < a.length - i - 1; j++)
            {
                if (a[j] > a[j + 1])
                {
                    int tmp = a[j + 1];
                    a[j + 1] = a[j];
                    a[j] = tmp;
                }
            }
        }
        System.out.println("排序结果");
        for (int i : a)
        {
            System.out.println(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 chap1;

import java.util.Scanner;

public class Main
{
    public static void main(String[] args)
    {
        int[] l = {34,22,35,67,45,66,12,33};
        System.out.println("请输入一个数字");
        Scanner s = new Scanner(System.in);
        int a = s.nextInt();
        boolean found = false;
        for (int i = 0; i < l.length; i++)
        {
            if (a == l[i])
            {
                found = true;
                System.out.println("下标为" + i);
                break;
            }
        }
        if (!found)
        {
            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 chap1;

public class Main
{
    public static void main(String[] args)
    {
        double[][] a = new double[][]{{1,2,3,4,5}, {6,7,8,9,10}, {11,12,13,14,15}, {16,17,18,19,20}};
        for (double[] i : a)
        {
            for (double j : i)
            {
                System.out.print(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 chap1;

public class Main
{
    public static void main(String[] args)
    {
        double[][] a = new double[][]{{1,2,3}, {6,7,8}, {11,12,13}, {16,17,18}};
        double max = 0;
        for (double[] i : a)
        {
            for (double j : i)
            {
                if (j > max)
                {
                    max = j;
                }
            }
        }
        System.out.println("最大值为" + max);
    }
}