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.
a = list(input().split(':'))
s = int(a[0]) * 60 + int(a[1])
a = list(input().split(':'))
t = int(a[0]) * 60 + int(a[1])
res = (24 * 60 + s - t)%(24*60)
h = res//60
m = res%60
ans = ""
if h < 10:
    ans += "0"
ans+= str(h)
ans+= ":"
if m < 10:
    ans += "0"
ans+= str(m)
print(ans)
