Java第七次作业
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 zj; public class text5 { /** * @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 zj; import java.util.Scanner; public class test5 { /** * @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(); } System.out.println("控制台输出"); for (int i = 0; i < a.length; i++) { System.out.print(" "+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 zj; public class text5 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub String []a={"c","h","i","n","a"}; 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 zj; import java.util.Scanner; public class test5 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub Scanner input=new Scanner(System.in); System.out.println("请输入5位学生的成绩"); int []a=new int [5]; double sum=0; double pj=0; for (int i = 0; i < a.length; i++) { a[i]=input.nextInt(); sum+=a[i]; pj=sum/5; } System.out.println("总分为"+sum); System.out.println("平均分为"+pj); } }
5.定义数组{12,53,23,44,53} 用for和foreach分别输出,再倒序输出
package zj; import java.util.Scanner; public class test5 { /** * @param args */ 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("for输出"); for (int i = 0; i < a.length; i++) { System.out.print(" "+a[i]); } System.out.println("\nforeach输出"); for (int i : a) { System.out.print(" "+i); } System.out.println("\n倒序输出"); for (int i = 4; i >=0; i--) { System.out.print(" "+a[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 zj; public class text5 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub int a[]={11,22,33,44,55}; int c=0; int b=0; for (int i = 0; i < a.length; i++) { if (a[i]%2==0) { b++; } if (a[i]%2!=0) { c++; } } System.out.println("偶数个数为"+b); System.out.println("奇数个数为"+c); } }
2.生成一个100长度数组,里面的数分别是1-100,并输出
package zj; public class text5 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub 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++) { if (i<33) { System.out.print(" "+a[i]); } else if (i==33) { System.out.println(" "+a[i]); } else if (i<66) { System.out.print(" "+a[i]); } else if (i==66){ System.out.println(" "+a[i]); } else if (i<=99) { System.out.print(" "+a[i]); } else if (i==100){ System.out.println(" "+a[i]); } else{} } } }
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 zj; import java.util.Scanner; public class test5 { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub Scanner input=new Scanner(System.in); System.out.println("请输入10位学生成绩"); 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++) { a[i]=a[i]+5; if (a[i]>100) { a[i]=100; } } System.out.println("加5分后"); for (int i = 0; i < a.length; i++) { System.out.print(a[i]+" "); } } }