hw10_5.java

Java程序设计实例

//10-5
abstract class Math
{
   int ans;
   void show(){
      System.out.println("ans="+ans);
   }
   abstract int add(int a,int b); //计算a+b
   abstract int sub(int a,int b); //计算a-b
   abstract int mul(int a,int b); //计算a*b
   abstract int div(int a,int b); //计算a/b
}

class Compute extends Math
{
   public int add(int a,int b) //计算a+b
   {
      ans=a+b;
      return 0;
   }
   public int sub(int a,int b) //计算a-b
   {
      ans=a-b;
      return 0;
   }
   public int mul(int a,int b) //计算a*b
   {
      ans=a*b;
      return 0;
   }
   public int div(int a,int b) //计算a/b
   {
      ans=a/b;
      return 0;
   }
}

public class hw10_5
{
   public static void main(String args[])
   {
      Compute cmp=new Compute();
      cmp.mul(3,5);
      cmp.show();
   }
}