using System;

namespace ConsoleHoursMinutesDegree
{
    class Program
    {
        public const int hoursToDegrees = 30;
        public const int minutesHoursToDegrees = 2;
        public const int minutesToDegrees = 6;
        public static double GetAngleHours(string time)
        {
            string timeGetAngleHours = time.Replace(":", " ");
            var parts = timeGetAngleHours.Split();
            int hours = int.Parse(parts[0]);
            if (hours > 12)
            {
                hours = hours - 12;
            }
            int minutes = int.Parse(parts[1]);
            double angleHours = hours * hoursToDegrees + minutes / minutesHoursToDegrees;
            return angleHours;
        }

        public static int GetAngleMinutes(string time)
        {
            string timeGetAngleMinutes = time.Replace(":", " ");
            var parts = timeGetAngleMinutes.Split();
            int minutes = int.Parse(parts[1]);
            int angleMinutes = minutes * minutesToDegrees;
            return angleMinutes;
        }

        public static void Main()
        {
            string time = Console.ReadLine();
            double angleHours = GetAngleHours(time);
            int angleMinutes = GetAngleMinutes(time);
            double angle = Math.Abs(angleHours - angleMinutes);
            if (angle > 180)
            {
                angle = 360 - angle;
            }
            Console.WriteLine(angle);
        }
    }
}