Question

public class OperationsBetween {
// You must define the following:
// 1.) Two private instance variables, min and max  
// 2.) A constructor which takes initial values for
// min and max
// 3.) An instance method named sum, which sums the
// values between min and max and returns the
// result. For example, if min = 3 and max = 5,
// then this should return 12 (3 + 4 + 5). If
// min is greater than max, then this should
// return 0.
//
// 4.) An instance method named product, which
// multiplies the values between min and max and
// returns the result. For example, if min = 6
// and max = 9, then this should return 3024
// (6 * 7 * 8 * 9). If min is greater than
// max, then this should return 1. A stub has
// been provided that simply returns 1; this is
// just to allow things to compile while you're
// working on the sum method.

public int product() {
// You'll need to replace this code with something
// else to make product() work; this is just to make
// things compile while you work on sum()
return 1;
}

// DO NOT MODIFY main!
public static void main(String[] args) {
OperationsBetween between =
new OperationsBetween(Integer.parseInt(args[0]),
Integer.parseInt(args[1]));
System.out.println("Sum: " + between.sum());
System.out.println("Product: " + between.product());
}
}

Answer 1

In the main function the program is taking command line argument. So wee need to run the program and pass in command line itself.

Have a look at the below code.

public class OperationsBetween{
  private int min,max;
  public OperationsBetween(int a, int b){

    this.min = a;

    this.max = b;

  }

  public int sum(){
    if (min>max){
      return 0;
    }
    int res = 0;

    for (int i=min;i<=max;i++){
      res+=i;
    }
    return res;
  }

  public int product(){

     if (min>max){
      return 1;
    }
    int res = 1;

    for (int i=min;i<=max;i++){
      res*=i;
    }
    return res;
  }

}
class Main {
  public static void main(String[] args) {
    OperationsBetween between =new OperationsBetween(Integer.parseInt(args[0]),Integer.parseInt(args[1]));
    System.out.println("Sum: " + between.sum());
    System.out.println("Product: " + between.product());
  }
}

Just complete the code. Then go to command line and compile you java code by running ...

javac filename.java 

Then run you java code by passing command line arguments...

java filename arg1 arg2 

Use your filename instead of filename and your arguments value of min max instead of arg1 and arg2.

Happy Learning!