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

namespace ConsoleApp3
{
    class Program
    {
        static void Main(string[] args)
        {
            var R = double.Parse(Console.ReadLine());
            var C = R * (180 / Math.PI);
            Console.WriteLine(Math.Round(C, 0));

        }
    }
}