# -*- coding: utf-8 -*-

#-------
# Initialize
hh, mm = map(int, input().split(":"))
mmup = 0

#-------
# Define

#-------
# Do
mm += 5
if (mm >= 60):
    mm -= 60
    mmup = 1
hh += mmup
if (hh >= 24):
    hh -= 24

#-------
# Output

print("{0:02d}".format(hh) + ":" + "{0:02d}".format(mm))