using System;

public class Program

{   

    public enum Operator

    {

       PLUS, MINUS, MULTIPLY, DIVIDE

    }   

    public static void Main()

    {

        Console.Write(Calculate(25,47,Operator.PLUS));

    }

    public static double Calculate(int left, int right, Operator op)

    {

    double sum = 0.0;

​

        switch(op)

        {

            case Operator.PLUS:

            sum = left + right;

            return sum;

​

            case Operator.MINUS:

            sum = left - right;

            return sum;

​

            case Operator.MULTIPLY:

            sum = left * right;

            return sum;

​

            case Operator.DIVIDE:

            sum = (double)left / right;

                return sum;

​

            default:

            return sum;

      }

    }   

}