第七周上机+练习4.16
上机:
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 week7; public class P1 { /** * @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 week7; import java.util.Scanner; public class P2 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub Scanner input=new Scanner(System.in); int a[]=new int[5]; 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 week7; public class P3 { /** * @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 week7; import java.util.Scanner; public class P4 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub Scanner input=new Scanner(System.in); double a[]=new double[5]; double sum=0; for (int i = 0; i < a.length; i++) { a[i]=input.nextInt(); } for (int i = 0; i < a.length; i++) { 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 week7; public class P5 { /** * @param args */ public static void 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]); }System.out.println(" "); for (int i = 4; i >0; i--) { System.out.println(a[i]); }System.out.println(" "); for(int i :a){ System.out.println(i); } } }
作业:
1.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 week7; public class W1 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub int a[]={23,54,43,76,23}; int sum=0; int um=0; for (int i = 0; i < a.length; i++) { if(a[i]/2==0) { sum++; } else { um++; } } System.out.println(sum+"个偶数"); System.out.println(um+"个奇数"); } }
2.生成一个100长度数组,里面的数分别是1-100,并输出
package week7; public class W2 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub int a[]=new int[100]; int b=0; for (int i = 0; i < a.length; i++) { b++; a[i]=b; 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 week7; public class W3 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub double a[]={54,87,65,54,98,97,76,54,65,78}; for (int i = 0; i < a.length; i++) { if(a[i]<=95&&a[i]>=0) { a[i]+=5; } else if(a[i]>95) { a[i]=a[i]; } System.out.println(a[i]); } } }