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 com.itheima01;
import java.util.Scanner;
public class Day01 {

    public static void main(String[] args) {    
          Scanner input = new Scanner(System.in);
             System.out.println("数组的值：");
             int[] a = new int[5];
             for(int i=0;i<a.length;i++){
             a[i]=input.nextInt();
            }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 temp = a[j];
                        a[j] = a[j+1];
                        a[j+1] = temp;
                    }
                }
            }System.out.println("冒泡排序后输出：");
            for(int 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 com.itheima01;
import java.util.Scanner;
public class Day01 {

    public static void main(String[] args) {    
           Scanner sc = new Scanner(System.in);
            boolean  z = false;
            int[] x = new int[]{34,22,35,67,45,66,12,33};
            System.out.print("请输出一个数：");
            int a = sc.nextInt();
            for(int i=0;i<x.length;i++){
                if(x[i]==a){
                    System.out.println("该数存在于数组中，下标为："+i);
                     z=true;
                }
            } if(z==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 com.itheima01;
import java.util.Scanner;
public class Day01 {

    public static void main(String[] args) {    
           double [][] arr = {{1,3,5,7},{2,4,6,8},
                      {9,1.1,1.3,1.5},{1.0,1.2,1.4,1.6},
                      {1.7,1.9,2.1,2.3}};
              for(int i=0;i<arr.length;i++){
                  System.out.println();
                  for(int j=0;j<arr.length-1;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 com.itheima01;
import java.util.Scanner;
public class Day01 {

    public static void main(String[] args) {    
        int arr[][] = {{1,2,3},{4,5,6},
                {7,8,9},{10,11,12}};
        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("该二维数组的最大值为:"+max);
        }

        }