import datetime
a, b, S = map(str, input().split())
m = (float(S[3:]) - 9) * 60
now = datetime.datetime(2018,9,4,int(a),int(b),)
now += datetime.timedelta(minutes = m)


print(str(now.hour).zfill(2) + ":" + str(now.minute).zfill(2))