Question

You are given the following Java files:

• EvaluateExprission that you will use to add a method.

In EvaluateExprission.java write a recursive method   

public static int EvaluateE (int x, int y)

The method should evaluate the expression bellow and take the values x, y from the user.

Update the main to call EvaluateE method properly .

E = xy +x* (x-1)(y-1) +x* (x-2)(y-2) + . . . +1

Answer 1

import java.util.*;

public class EvaluateExprission
{
//recursive method to calculate the sum of the series
public static int EvaluateE (int x, int y)
{
//base condition
if(x*y < 1)
return 0;
  
//recursive call
return x*y + x * EvaluateE(x-1, y-1);
}
  
   public static void main(String[] args)
   {
   Scanner sc = new Scanner(System.in);
  
   //get user input
   System.out.println("Enter the value of x and y:");
   int x = sc.nextInt();
   int y = sc.nextInt();
  
   //method calline
   int E = EvaluateE(x, y);
  
   //display the result
       System.out.println("The sum of the series is = "+E);
   }
}

OUTPUT:

Enter the value of x and y:
2 2
The sum of the series is = 6