import sys
from math import sqrt, pi, sin, factorial
inp = lambda : sys.stdin.readline()[:-1]
mii = lambda x = " ": [*map(int,inp().split(x))]
mfi = lambda x = " ": [*map(float,inp().split(x))]
ii = lambda : int(inp())
h, m = mii(":")
n = ii()
t = h* 60 + m
cnt = 0
while 1:
if t % 60 == 0:
k = (t // 60) % 12
if k == 0:
k = 12
cnt += k
elif t % 15 == 0:
cnt += 1
if cnt >= n:
break
t += 1
h = (t // 60) % 12
if h == 0:
h = 12
print(f"{h:02d}:{t%60:02d}")