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/12 * 360 + m/60 * 30
ma = m/60 * 360
if ha>ma:
	ans = ha - ma
else:
	ans = ma - ha
if(ans>180):
	ans = 360 - ans
print '%.6f' %ans