h, s, tz = input().split()
h, s = map(int, [h,s])
a = 1
if tz[3] == "-":
    a = -1
if "." in tz:
    h_tz, s_tz = map(int,tz[4:].split("."))
else:
    h_tz, s_tz = int(tz[4:]), 0


tz = (h_tz*60+s_tz*6)*a

s = (60*h+s-540+tz) % (24*60)

h, s = map(str, [s // 60, s % 60])
if len(s) == 1:
    s = "0" + s
if len(h) == 1:
    h = "0" + h
print(h+":"+s)