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 = list(map(int, input().split(":")))
t = list(map(int, input().split(":")))

ms = s[0] * 60 + s[1]
mt = t[0] * 60 + t[1]

if ms >= mt:
    h, m = divmod(ms - mt, 60)
    print(f"{h:02}:{m:02}")
else:
    h, m = divmod(ms + 24 * 60 - mt, 60)
    print(f"{h:02}:{m:02}")
