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 work;

import java.util.*;

public class wjb {

    public static void main(String[] args) {
        int[] a = new int[5];
        int i, j;
        int temp;
        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]) {
                    temp = a[j];
                    a[j] = a[j + 1];
                    a[j + 1] = temp;
                }
            }
        }
        System.out.println("排序后:");
        for (i = 0; i < a.length; i++) {
            System.out.println(a[i] + "\t");
        }
    }
}

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 work;

import java.util.*;

import javax.swing.plaf.synth.SynthSpinnerUI;

public class wjb {

    public static void main(String[] args) {
        Scanner input=new Scanner(System.in);
        int[] x={34,22,35,67,45,66,12,33};
        System.out.println("请输入一个数:");
        int a=input.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);
            }else{
                System.out.println("not found");
            }break;
        }        
    }
}

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 work;

import java.util.*;

public class wjb {

    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        int[][] a = new int[5][4];
        int m = 0;
        for (int i = 0; i < 5; i++) {
            for (int j = 0; j < 4; j++) {
                a[i][j] = m;
                m++;
            }
        }
        System.out.println("你输入的数组为:");
        for (int i = 0; i < 5; i++) {
            for (int j = 0; j < 4; j++) {
                System.out.print(a[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 work;

import java.util.*;

public class wjb {

    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        int[][] a = new int[5][4];
        int m = 0;
        int max=0;
        for (int i = 0; i < 3; i++) {
            for (int j = 0; j < 4; j++) {
                a[i][j] = m;
                m++;
            }
        }
        for (int i = 0; i < a.length; i++) {
            for (int j = 0; j < a[i].length-1; j++) {
                if(max<a[i][j]){
                    max=a[i][j];                    
                }
            }
        }
        System.out.println("最大值是:"+max);
    }
}