using System;

  class Rational

    {

        public int num;

        public int denum;

        public double dec;

        public void Add(Rational r)

        {

            this.num = this.num * r.denum + r.num * this.denum;

            this.denum = this.denum * r.denum;

        }

        public void Sub(Rational r)

        {

            this.num = this.num * r.denum - r.num * this.denum;

            this.denum = this.denum * r.denum;

        }

        public void Mult(Rational r)

        {

            this.num = this.num * r.num;

            this.denum = this.denum * r.denum;

        }

        public void Div(Rational r)

        {

            this.num = this.num * r.denum;

            this.denum = this.denum * r.num;

        }

        public int Compare(Rational r)

        {

            if (this.num*r.denum>r.num*this.denum)

            {

                return 1;

            }

            if (this.num * r.denum < r.num * this.denum)

            {

                return -1;

            }

            return 0;

        }

       public double Dec()

       {

          return this.dec =(double) this.num / this.denum;

        }

        public void Print(Rational r)

        {

            this.dec = (double)this.num / this.denum;

            Console.WriteLine(this.dec);

        }

    }                   

public class Program

{

    public static void Main()

    {

        Rational x = new Rational();

            Console.Write("numx=");x.num = int.Parse(Console.ReadLine());

            Console.Write("denumx=");x.denum = int.Parse(Console.ReadLine());

            Rational y = new Rational();

            Console.Write("numy="); y.num = int.Parse(Console.ReadLine());

            Console.Write("denumy="); y.denum = int.Parse(Console.ReadLine());

            Console.WriteLine("Въведете операция: ");

            Console.WriteLine("1 - събиране (x+y)");

            Console.WriteLine("2 - изваждане (x-y)");

            Console.WriteLine("3 - умножение (x.y)");

            Console.WriteLine("4 - деление (x/y)");

            Console.WriteLine("5 - сравняване (x vs y)");

            Console.WriteLine("6 - x като десетична дроб");

            Console.WriteLine("7 - y като десетична дроб");

            var i = int.Parse(Console.ReadLine());

            Console.WriteLine("Резултат:");

            switch (i)

            {

                case 1: x.Add(y);

            Console.Write("x+y=");x.Print(y);break;

                case 2:

                    x.Sub(y);

                    Console.Write("x-y="); x.Print(y);break;

                case 3:

                    x.Mult(y);

                    Console.Write("x*y="); x.Print(y); break;

                case 4:

                    x.Div(y);

                    Console.Write("x/y="); x.Print(y); break;

                case 5:

​

                    Console.Write("x vs y={0}", x.Compare(y)); break;

                case 6: 

                    x.Dec();

                    Console.Write("x="); x.Print(x); break;

                case 7:

                    y.Dec();

                    Console.Write("y="); y.Print(y); break;

                default:

                    break;

            }

    }

}