import re

T = input()
match = re.match(r'(\d\d):(\d\d)', T)
h, m = int(match.group(1)), int(match.group(2))

m += 5

if m >= 60:
	h += 1
	m %= 60

if h == 24:
	h = 0

print('{0:02d}:{1:02d}'.format(h, m))