第七周作业

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

package test;

public class test_1 {

	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 test;

import java.util.Iterator;
import java.util.Scanner;

public class test_1 {

	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++) {
			System.out.println("请输入第"+(i+1)+"个数");
			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 test;

import java.util.Iterator;
import java.util.Scanner;

public class test_1 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		char a[]= {'c','h','i','n','a'};
		for (char i:a) {
			System.out.print(i);
		}
		}

	}

　　

4.输入5个学生成绩，求总分和平均分

package test;

import java.util.Iterator;
import java.util.Scanner;

public class test_1 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner input = new Scanner(System.in);
		double[] s = new double[5];
		for (int i = 0; i < s.length; i++) {
			System.out.println("输入第" + (i + 1) + "个学生成绩");
			s[i] = input.nextDouble();
		}
		int sum=0;
		for (int i = 0; i < s.length; i++) {
			sum+=s[i];
		}
		System.out.println("学生总成绩为"+sum);
		System.out.println("学生成绩的平均值"+(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 test;

import java.util.Iterator;
import java.util.Scanner;

public class test_1 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner input = new Scanner(System.in);
		int a[]= {12,53,23,44,53};
		for (int i = 0; i < a.length; i++) {
			System.out.println(a[i]);
		}
		System.out.println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
		for (int i : a) {
			System.out.println(i);
		}

		}

	}

　　

package test;

import java.util.Iterator;
import java.util.Scanner;

public class test_1 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner input = new Scanner(System.in);
		int a[]= {12,53,23,44,53};
		System.out.println(a[4]);
		System.out.println(a[3]);
		System.out.println(a[2]);
		System.out.println(a[1]);
		System.out.println(a[0]);

		}

	}

　　

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 test;

import java.util.Iterator;
import java.util.Scanner;

public class test_1 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner input = new Scanner(System.in);
		int a[]= {2,5,9,6,7,3,8,44,19,9};
		int ou=0,ji=0;
		for (int i = 0; i < a.length; i++) {
			if(a[i]%2==0)
				ou++;
			else
			    ji++;
		}
		System.out.println("偶数个数是"+ou);
		System.out.println("奇数个数是"+ji);
		}
 
	}

　　

7.生成一个100长度数组，里面的数分别是1-100，并输出

package test;

 

import java.util.Iterator;

import java.util.Scanner;

 

public class test_1 {

 

    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]);

        }

        }

 

    }

 

 

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 测试;

import java.util.Scanner;

public class test {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		double[] scores = {80.5, 90.0, 75.5, 85.0, 95.5, 70.0, 60.5, 88.0, 92.5, 87.0};
        for (int i = 0; i < scores.length; i++) {
            scores[i] += 5;
            if (scores[i] > 100) {
                scores[i] = 100;
            }
        }
        for (double score : scores) {
            System.out.println(score);
        }