第四次作业

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 come.itheima01;
import java.util.Scanner;
public class Sz {

    public static void main(String[] args) {
        Scanner sc=new Scanner(System.in);
        int[] a = new int[5];
        int i, j;
        int k;
        Scanner input = new Scanner(System.in);
        System.out.println("请输入5个整数:");
        for (i = 0; i < 5; i++) {
        a[i] = input.nextInt();
        }
        for (i = 0; i < a.length - 1; i++) {
        for (j = 0; j < a.length - 1 - i; j++) {
        if (a[j] > a[j + 1]) {
        k = a[j];
        a[j] = a[j + 1];
        a[j + 1] = k;
        }
        }
        }
        System.out.println("冒泡排序:");
        for (i = 0; i < a.length; i++) {
        System.out.println(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 come.itheima01;
import java.util.Scanner;
public class Sz {
    public static void main(String[] args) {
        Scanner a=new Scanner(System.in);
        int[] b = { 34, 22, 35, 67, 45, 66, 12, 33 };
        int k = -1;
        System.out.println("输入一个数");
        int c = a.nextInt();
        for (int i = 0; i < b.length; i++) {
        if (b[i] == c) {
        k = i;
        System.out.println("下标为" + i);
        break;
        }
        }
        if (k == -1) {
        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 come.itheima01;
import java.util.Scanner;
public class Sz {
    public static void main(String[] args) {

        double[][] a = {{1.1,2.2,3.2,4.4},{6.6,7.7,8.8,9.9},{12.1,13.5,14.5,15.5},{16.5,17.8,18,19.4},{11.2,12.2,13.3,14.4}};
        for(int i = 0;i < 5;i++) {
        for(int k = 0;k < 4;k++) {
        System.out.print(a[i][k]+" "); 
        }
        System.out.println();
        }
        }
        }

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 come.itheima01;
import java.util.Scanner;
public class Sz {
    public static void main(String[] args) {

        int[][] arr = {{10,21,31,14},{15,26,38,47},{18,24,83,46}};
        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(max);
    }

}