import sys
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines

s = readline().decode().strip()

splitted = s.split(":")
h = int(splitted[0])
m = int(splitted[1])

m += 5
add = m // 60
m %= 60
h += add
h %= 24

print("{}:{}".format(str(h).zfill(2), str(m).zfill(2)))