n, m, t = int(input()), int(input()), int(input()) n += t // 60 m += t % 60 while m > 59: m -= 60 n += 1 while n > 23: n -= 24 s = "" for arg in [n, m]: if arg < 10: s += "0" s += str(arg) s = s[:2] + ":" + s[2:] print(s)