a, b, s = input().split()

a = int(a)
b = int(b)
t = a * 60 + b
if len(s) == 5:
    x = int(s[3:])
else:
    x = float(s[3:])
x *= 60
x = int(x)
d = x - 60 * 9
t += d
if t < 0:
    t += 24 * 60
elif t >= 24 * 60:
    t -= 24 * 60
h, m = divmod(t, 60)
print(f"{h:02}:{m:02}")