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(":")]
d=[int(x) for x in input().split(":")]
if s[1]<d[1]:
    s[0]-=1
    s[1]+=60
if s[0]<d[0]:
    s[0]+=24
if s[0]-d[0]<10:
    print("0",end='')
print("{0}:".format(s[0]-d[0]),end='')
if s[1]-d[1]<10:
    print("0",end='')
print("{0}".format(s[1]-d[1]),end='')
