第七周上机练习+作业

上机练习

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 Test4;

public class h1 {

    /**
     * @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 Test4;

import java.util.Scanner;

public class h1 {

    /**
     * @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 Test4;

import java.util.Scanner;

public class h1 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        String[] a = new String[5];
        Scanner input = new Scanner(System.in);
        System.out.println("请分别输入字母：");
        for (int i = 0; i < a.length; i++) {
            a[i] = input.next();
        }
        for (int i = 0; i < a.length; i++) {
            System.out.print(a[i]);
        }
    }

}

 

 

 4.输入5个学生成绩，求总分和平均分

package Test4;

import java.util.Scanner;

public class h1 {

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

package Test4;

public class h1 {

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

 

 

 作业：
1.定义一个整型数组，赋值后求出奇数个数和偶数个数

package Test4;

import java.util.Scanner;

public class h1 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int number1 = 0;
        int number2 = 0;
        int a[] = new int[5];
        Scanner input = new Scanner(System.in);
        System.out.println("请输入5个数:");
        for (int i = 0; i < a.length; i++) {
            a[i] = input.nextInt();
            if (a[i] % 2 == 0) {
                number1++;
            } else {
                number2++;
            }
        }
        System.out.println("偶数个数有:" + number1);
        System.out.println("奇数个数有:" + number2);
    }
}

 

 

 2.定义一个数组，求数组中的最大值和最小值

package Test4;

import java.util.Scanner;

public class h1 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int min = 0;
        int max = 0;
        int a[] = new int[5];
        Scanner input = new Scanner(System.in);
        System.out.println("请输入5个数:");
        for (int i = 0; i < a.length; i++) {
            a[i] = input.nextInt();
            min = a[0];
            max = a[0];
            if (a[i] > max) {
                max = a[i];
            }
            if (min > a[i]) {
                min = a[i];
            }
        }
        System.out.println("最小值为:" + min);
        System.out.println("最大值为:" + max);
    }
}

 

 

 2.生成一个100长度数组，里面的数分别是1-100，并输出

package Test4;

import java.util.Scanner;

public class h2two {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner input = new Scanner(System.in);
        int a[] = new int[100];
        for (int i = 0; i < a.length; i++) {
            a[i] = i + 1;
        }
        for (int i = 0; i < a.length; i++) {
            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 Test4;

import java.util.Scanner;

public class h3 {

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

}