Java7

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 a;

public class aaa {

    public static void main(String[] args) {
        int a[]= {10,20,30,40,50};
        for(int i :a) {
        System.out.println(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 prac;

import java.util.Scanner;

public class prac2 {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner input=new Scanner(System.in);
        System.out.println("请输入数组的值");
        int []a=new int[5];
        for (int i = 0; i < a.length; i++) {
            a[i]=input.nextInt();
        }
        System.out.println("数组的值为");
            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 prac;

public class prac3 {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        String []f= {"c","h","i","n","a"};
        for (int e = 0; e< f.length; e++) {
            System.out.println(f[e]);
        }
    }

}

 

4.输入5个学生成绩，求总分和平均分

package prac;

import java.util.Scanner;

public class prac4 {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner input=new Scanner(System.in);
        int sum=0;
        int []a=new int[5];
        for (int i = 0; i < a.length; i++) {
            System.out.println("请输入第"+(i+1)+"个学生的成绩");
            a[i]=input.nextInt();
        }
        for (int i = 0; i < a.length; i++) {
            sum+=a[i];
                
    }
        System.out.println("sum="+sum);
        System.out.println("aver="+sum/a.length);
    }

 

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

package prac;

public class prac5 {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
            int []a= {12,53,22,44,53};
/*            System.out.println("正常输出为");
            for (int i = 0; i < a.length; i++) {
                System.out.println(a[i]);
            }
            System.out.println("倒序输出为");
            for (int i =a.length-1; i>=0; i--) {
                System.out.println(a[i]);
            }
*/
            for (int i : a) {
                System.out.println(i);
            }

 

 

 

 

    }

}
6定义一个整型数组，赋值(动态静态都可以)后求出奇数个数和偶数个数

package prac;

public class prac6 {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int []a= {1,2,3,4,5,6,8,9,10,12,13};   
        int j=0;
        int o=0;
        for (int i = 0; i < a.length; i++) {
            if (a[i]%2==0) {
                o++;
            }else {
                j++;    
            }
        }
        System.out.println("奇数为"+j+"个");
        System.out.println("偶数为"+o+"个");
    }    

}

 

7.生成一个100长度数组，里面的数分别是1-100，并输出

 

package prac;

public class prac7 {

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

}

 

8.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 prac;

import java.util.Scanner;

public class prac8 {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner input=new Scanner(System.in);
        System.out.println("输入学生成绩");
             double []a=new double[10];
             for (int i = 0; i < a.length; i++) {
                a[i]=input.nextDouble();
            }
             for (int i = 0; i < a.length; i++) {
                if (a[i]+5>=100) {
                System.out.println(100);
            }else if(a[i]+5>0)
                System.out.println(a[i]+5);
            }
    }

}