using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace template
{
    class Program
    {
        static void Main(string[] args)
        {
            long n = long.Parse(Console.ReadLine());
            n /= 1000;
            Console.WriteLine(n / int.Parse(Console.ReadLine()) * 1000);
        }
    }
}