black flag

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Threading;

namespace ConsoleApp1
{
    class Exam
    {
        static void Main(string[] args)
        {
            int days = int.Parse(Console.ReadLine());
            int daily = int.Parse(Console.ReadLine());
            int expected = int.Parse(Console.ReadLine());

            double sum = 0;

            for (int i = 1; i <= days; i++)
            {
                sum += daily;

                if (i % 3 == 0)
                {
                    sum += daily * 0.50;
                }

                if (i % 5 == 0)
                {
                    sum -= (sum * 0.30);
                }

            }

            if (sum >= expected)
            {
                Console.WriteLine($"Ahoy! {sum:f2} plunder gained.");
            }
            else
            {
                double percentage = (sum / expected) * 100.0;
                Console.WriteLine($"Collected only {percentage:f2}% of the plunder.");
            }
        }
    }
}