Java第七周上机练习＋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。

packageaaa;

publicclass Text1 {

    /**
     * @paramargs
     */
    publicstaticvoid 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。

packageaaa;

importjava.util.Scanner;

publicclass Text2 {

    /**
     * @paramargs
     */
    publicstaticvoid main(String[] args) {
        // TODO Auto-generated method stub
        Scanner input=newScanner(System.in);
        int []a=newint[5];
        for (int i = 0; i <a.length; 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

packageaaa;

publicclass Text3 {

    /**
     * @paramargs
     */
    publicstaticvoid main(String[] args) {
        // TODO Auto-generated method stub
        char[] b = {'c','h','i','n','a' };
        for (int i = 0; i <b.length; i++) {
            System.out.println(b[i]);
        }

    }

}

 

 

4.输入5个学生成绩，求总分和平均分

packageaaa;

importjava.util.Scanner;

publicclass Text4 {

    /**
     * @paramargs
     */
    publicstaticvoid main(String[] args) {
        // TODO Auto-generated method stub
        Scanner input = newScanner(System.in);
        int[] a = newint[5];
        int sum = 0;
        doublepj = 0;
        for (int i = 0; i <a.length; i++) {
            a[i] = input.nextInt();
            sum += a[i];
            pj = sum / 5;

        }
        System.out.println(sum);
        System.out.println(pj);

    }

}

 

 

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

packageaaa;

publicclass Text5 {

    /**
     * @paramargs
     */
    publicstaticvoid main(String[] args) {
        // TODO Auto-generated method stub
        int[] a = { 12, 53, 23, 44, 53 };
        for (int i = 0; i <a.length; i++) {
            System.out.println(a[i]);
        }

    }

}

 

 

packageaaa;

publicclass Text5 {

    /**
     * @paramargs
     */
    publicstaticvoid main(String[] args) {
        // TODO Auto-generated method stub
        int[] a = { 12, 53, 23, 44, 53 };
        for (int i : a) {
            System.out.println(i);
        }

    }

}

 

 

packageaaa;

publicclass Text5 {

    /**
     * @paramargs
     */
    publicstaticvoid main(String[] args) {
        // TODO Auto-generated method stub
        int[] a = { 12, 53, 23, 44, 53 };
        for (int i=4; 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

packageaaa;

publicclass Text6 {

    /**
     * @paramargs
     */
    publicstaticvoid main(String[] args) {
        // TODO Auto-generated method stub
        int[] a = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };
        intjs = 0;
        intos = 0;
        for (int i = 0; i <a.length; i++) {
            if (a[i] % 2 == 0) {
                os++;
            }
            if (a[i] % 2 != 0) {
                js++;
            }
        }
        System.out.println(os);
        System.out.println(js);
    }

}

 

 

2.生成一个100长度数组，里面的数分别是1-100，并输出

package practise3;

public class Test1 {

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

}

 

......

 

 

 

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 practise3;

import java.util.Scanner;


public class Test1 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
         double a[] = new double[10];
            double sum = 0;
            Scanner input = new Scanner(System.in);
            for (int i = 0; i < a.length; i++) {
                System.out.println("输入第" + (i + 1) + "个学生成绩");
                a[i] = input.nextInt();
            }
            for (int i = 0; i < a.length; i++) {
                sum = a[i] + 5;
                if (sum >= 100) {
                    System.out.println("加分后成绩为100分");
                } else {
                    System.out.println("加分后成绩为" + sum + "分");
                }
            }
    }

}