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
h,m=map(float,raw_input().split(':'))
h=h%12
ha=(h*30)+(0.5*m)
ma=m*6
res=abs(ha-ma)
if res>180:
	print '%.6f' % float(360.0-res)
else:
	print '%.6f' % res