# Add time

def hms(s):

dd = dict(zip([1, 60, 360], [float(i) for i in s.split(':')]))

return sum([f/v for v, f in dd.items()])

def main():

origTime = raw_input("Enter clock time (hh:mm): ")

hrsAdd = raw_input("Enter hours to add (hh:mm): ")

return hms(origTime) + hms(hrsAdd)

print main()