Why I have Runtime error? I use C#. Code is here.
using System;
using System.Globalization;

class EntryPoint
{
    static void Main()
    {
        CultureInfo ci = new CultureInfo("en-US");
        double p = Convert.ToDouble(Console.ReadLine(),ci);
        double q = Convert.ToDouble(Console.ReadLine(),ci);
        int x = 1;
        while (true)
        {
            if ((int)(q * x / 100) - (int)(p * x / 100) > 0)
                break;
            x++;
        }
        Console.WriteLine(x);
    }
}

Quote from problem description:
"These numbers are separated by some spaces or "end of line" symbols"