George woke up and saw the current time *s* on the digital clock. Besides, George knows that he has slept for time *t*. 

Help George! Write a program that will, given time *s* and *t*, determine the time *p* when George went to bed. Note that George could have gone to bed yesterday relatively to the current time (see the second test sample).
The first line contains current time *s* as a string in the format "hh:mm". The second line contains time *t* in the format "hh:mm" — the duration of George's sleep. It is guaranteed that the input contains the correct time in the 24-hour format, that is, 00 ≤ *hh* ≤ 23, 00 ≤ *mm* ≤ 59.
string = input()
time = string.split(":")
a, b = int(time[0]), int(time[1])
string = input()
time = string.split(":")
h, m = int(time[0]), int(time[1])
x = a * 60 + b
y = h * 60 + m
if x < y:
    x += 1440
t = x - y
temp = t // 60 % 24
p = str(temp)
if temp < 10:
    p = "0" + p
temp = t % 60
q = str(temp)
if temp < 10:
    q = "0" + q
print("%s:%s" % (p, q))