a,b,s = input().split()
t = 60*(int(a)-9)  + int(round(float(s[3:])*60)) + int(b)
t %= 1440
a,b = str(t//60), str(t%60)
a = "0"*(2-len(a)) + a
b = "0"*(2-len(b)) + b
print(f"{a}:{b}")