using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("紅茶10元、奶茶15元、咖啡20元，請問使用者需要買幾杯飲料?");

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

        int total=0;

        for(int i=1;i<=num;i=i+1)

        {

            Console.WriteLine("第"+i+"杯要要喝甚麼，紅茶輸入1，奶茶輸入2，咖啡輸入3");

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

            if(C == 1)

            {

                 total = total + 10;

            }

            else if(C == 2)

            {

                 total= total +15;

            }

            else if(C == 3)

            {

                 total= total +20;

            }

        }

        Console.WriteLine("總共"+total+"元");

    }

}