Java第七次作业

1.编写一个简单程序，要求数组长度为5，静态赋值10，20，30，40，50，在控制台输出该数组的值。

public class Exe01 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int[] x = { 10, 20, 30, 40, 50 };
        for (int i = 0; i < 5; i++) {
            System.out.println(x[i]);
        }
    }

}

 

2.编写一个简单程序，要求数组长度为5，动态赋值，并在控制台输出该数组的值。

import java.util.Scanner;

public class Exe01 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int[] a = new int[5];
        Scanner input = new Scanner(System.in);
        for (int i = 0; i < 5; i++) {
            a[i] = input.nextInt();
            System.out.println(a[i]);
        }
    }
}

 

 3.定义字符型数组，分别存储c、h、 i、n、a 并在控制台输出

public class Exe02 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        String a[] = new String[] { "c", "h", "i", "n", "a" };

        for (int i = 0; i < a.length; i++) {

            System.out.println(a[i]);
        }
    }
}

 

 4.输入5个学生成绩，求总分和平均分

import java.util.Scanner;

public class Exe02 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int[] a = new int[5];
        double sum=0;
        Scanner input = new Scanner(System.in);
        for (int i = 0; i < 5; i++) {
            a[i] = input.nextInt();
            sum+=a[i];

        }
        System.out.println("总分为"+sum);
        System.out.println("平均分为"+sum/5);
    }
}

 

 5.定义数组{12,53,23,44,53} 用for和foreach分别输出，再倒序输出(for)

public class Exe02 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int[] x = { 12, 53, 23, 44, 53 };
        for (int i = 0; i < 5; i++) {
            System.out.print(x[i]+" ");
        }
        System.out.println();
        System.out.println("-----------------");
        for (int i = 4; i >=0; i--) {
            System.out.println(" ");
            System.out.println(x[i]);
        }
    
    }

}

 

public class Exe02 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int[] x = { 12, 53, 23, 44, 53 };
        for (int i : x) {
    
            System.out.print(i+" ");
        }
        System.out.println();
        System.out.print("-------------------------");
        for (int i = 4; i >=0; i--) {
            System.out.println(" ");
            System.out.println(x[i]);
        }
    
    }

}

 

 

作业：

1.定义一个长度为10的整型数组，赋值(动态静态都可以)后求出奇数个数和偶数个数

import java.util.Scanner;

public class text {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int[] a =new int[10];
        int x=0,y=0;
        Scanner input = new Scanner(System.in);
        for (int i = 0; i <= 9; i++) {
            a[i]=input.nextInt();
        }
        for(int j=0;j<=9;j++){
            if(a[j]%2==0){
                x++;
            }
            if(a[j]%2!=0){
                y++;
            }
        }
        System.out.println("奇数个数为"+y+","+"偶数个数为"+x);
    }

}

 

 

2.生成一个100长度数组，里面的数分别是1-100，并输出

import java.util.Scanner;

public class text {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int[] a = new int[100];
        int x = 0, y = 0;
        Scanner input = new Scanner(System.in);
        for (int i = 0; i <= 99; i++) {
            a[i] = i + 1;
        }
        for (int j = 0; j <= 99; j++) {
            System.out.println(a[j]);
        }
    }

}   

 

 

 

3.定义一个double数组，存放10个学生的成绩，给所有同学加5分，不能超过100分。

import java.util.Scanner;

public class text {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        double[] a = new double[10];
        Scanner input = new Scanner(System.in);
        for (int i = 0; i <= 9; i++) {
            a[i] = input.nextDouble();
            for (int y = 0; y < 1;) {
                if (a[i] > 100 | a[i] < 0) {
                    System.out.println("输入错误重新输入");
                    a[i] = input.nextDouble();
                }
                if (a[i] >= 0 & a[i] <= 100) {
                    break;
                }

            }
        }
        for (int j = 0; j <= 9; j++) {
            a[j] += 5;
            if (a[j] > 100) {
                a[j] = 100;
            }
            System.out.println(a[j]);
        }
    }
}