import math
hour = int(input())
minutes = int(input())
minutes1 = hour * 60 + minutes + 15
hour1 = minutes1 / 60
hour2 = math.floor(hour1 % 24)
minutes2 = minutes1 % 60

if minutes2 < 10:
    print(f'{hour2}:0{minutes2:.0f}')
else:
    print(f'{hour2}:{minutes2:.0f}')