Java第七周上机练习作业

 

练习

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。

 

package Third;

public class D1 {

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

package Third;

import java.util.Scanner;

public class D2 {

    /**
     * @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 < a.length; i++) {
            a[i] = input.nextInt();
        }
        for (int i = 0; i < a.length; i++) {
            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

 

package Third;

public class D3 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        char[] a = { '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

 

package Third;

import java.util.Scanner;

public class D4 {

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

}

 

 

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

 

package Third;

public class D5 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int[] a = { 12, 53, 23, 44, 53 };
        System.out.println("for输出");
        for (int i = 0; i < a.length; i++) {
            System.out.println(a[i]);
        }
        System.out.println("foreach输出");
        for (int i : a) {
            System.out.println(i);
        }
        System.out.println("倒序输出");
        for (int i = a.length - 1; i >= 0; i--) {
            System.out.println(a[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

 

package Third;

import java.util.Scanner;

public class D6 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner input = new Scanner(System.in);
        int[] a = new int[10];
        int jishu = 0;
        int oushu = 0;
        for (int i = 0; i < a.length; i++) {
            a[i] = input.nextInt();
            if (a[i] % 2 == 0) {
                oushu++;
            } else {
                jishu++;
            }
        }
        System.out.println("奇数有" + jishu + "个");
        System.out.println("偶数有" + oushu + "个");
    }

}

 

 

 2.生成一个100长度数组，里面的数分别是1-100，并输出

 

package Third;

public class D7 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int a[] = new int[100];
        for (int i = 0; i < a.length; i++) {
            a[i] = i;
            System.out.print(a[i] + 1 + " ");
        }

    }
}

 

 

 

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。

 

package Third;

import java.util.Scanner;

public class D8 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner input = new Scanner(System.in);
        double[] g = new double[10];

        for (int i = 0; i < g.length; i++) {
            g[i] = input.nextDouble();
        }
        for (int i = 0; i < g.length; i++) {
            if (g[i] + 5 >= 100) {
                System.out.println(100);
            } else {
                System.out.println(g[i] + 5);
            }

        }
    }
}