// Erasto U. Samarinta

// BSIT 3-2N

// ADET

​

using System;

namespace midterm {

    public abstract class CalculatorBase {

        public abstract float add(float a, float b);

        public abstract float subtract(float a, float b);

        public abstract float multiply(float a, float b);

        public abstract float divide(float a, float b);

    }

​

    public class Calculator : CalculatorBase {

        public override float add(float a, float b) {

            return a + b;

        }

        public override float subtract(float a, float b) {

            return a - b;

        }

        public override float multiply(float a, float b) {

            return a * b;

        }

        public override float divide(float a, float b) {

            return a / b;

        }

    }

    public class Program

    {

        public static void Main()

        {

            Calculator calc = new Calculator();

            Console.WriteLine(calc.add(6, 9));

            Console.WriteLine(calc.subtract(6, 9));

            Console.WriteLine(calc.multiply(6, 9));

            Console.WriteLine(calc.divide(6, 9));

        }

    }

}