# -*- coding: utf-8 -*-
import datetime

# 1. 入力情報取得.
T = str(input())

# 2. 二度寝の時刻.
d = "2019/02/14 " + T + ":00";
dd = datetime.datetime.strptime(d, '%Y/%m/%d %H:%M:%S')
ans = dd + datetime.timedelta(minutes=5)

# 3. 出力.
print("{0:%H:%M}".format(ans))