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=[int(i)for i in input().split(':')]
b=[int(i)for i in input().split(':')]
c=a[0]-b[0]
d=a[1]-b[1]
if c<0:c+=24
if c<10:print('0',end='')
print(c,end='')
print(':',end='')
if d<0:d+=60
if d<10:print('0',end='')
print(d,end='')
