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.
s = [int(x) for x in input().split(":")]
t = [int(x) for x in input().split(":")]
s1 = s[0] * 60 + s[1] + 1440
t1 = t[0] * 60 + t[1]
p = (s1 - t1) % 1440
print("0" * (2 - len(str(p // 60))) + str(p // 60) + ":" + "0" * (2 - len(str(p % 60))) + str(p % 60))