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 + m/2
ma = 6*m
ans = abs(ha - ma)
if(ans>180):
	ans = 360 - ans
print '%.6f' %ans