RADIANS

namespace Radians
{

    public static class Program
    {
        public static void Main()
        {
           double L = Double.Parse(Console.ReadLine());
           double W = Double.Parse(Console.ReadLine());
           double A = Double.Parse(Console.ReadLine());

           double roomSize = (L*100)*(W*100);
           double wardrobeSize = (A*100)*(A*100);
           double benchSize = roomSize/10;
           double free = roomSize- wardrobeSize- benchSize;
           double dancers = free/(40+7000);

           Console.WriteLine(Math.Round(dancers));
        }
    }