Given the time shown by a wall clock, you have to output the internal angle between the minute and hour hand of the clock.
(Wall Clock displays a 12 hour format.)

For instance, if the time shown is 01:00 , the angle between the hands is 30 degrees.

Input : Time in HH:MM format 
Output: The angle in degrees, correct up to 6 places of decimal.

SAMPLE INPUT
04:00

SAMPLE OUTPUT
120.000000
i = raw_input()

hour = int(i.split(":")[0])
minute = int(i.split(":")[1])


def clockangles(hour, minute):
    ans = abs((hour * 30 + minute * 0.5) - (minute * 6))
    return min(360-ans,ans)

a = clockangles(hour, minute)

print("%6f"%a)