T = input()
time = int(T[:2])*60 + int(T[-2:]) + 5
hour = time//60
minute = time%60
if hour >= 24:
    hour -= 24
if hour < 10:
    hour = '0'+str(hour)
if minute < 10:
    minute = '0'+str(minute)
print(str(hour)+':'+str(minute))