using System;

public class Program

{

    public static void Main()

    {

        Console.Write("Input total price        :  ");

        double price = double.Parse(Console.ReadLine());

        Console.Write("Do you have coupon  : ");

        char coupon = char.Parse(Console.ReadLine());

        if(coupon=='y'||coupon=='Y'){

            Console.Write("How many coupon discount(%): ");

            int dis = int.Parse(Console.ReadLine());

            price = price - ((dis/100)*price) ;

        }else{

            price *= 0.97 ;

        }

        Console.WriteLine("");

        Console.WriteLine("Total price : {0:n} Baht",price);

    }

}