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=input()
t=input()
s=s.split(':')
t=t.split(':')
x=''
h=int(s[0])-int(t[0])
m=int(s[1])-int(t[1])
if h<0:
    h=24+h 
if len(str(h))==1:
    x+='0'+str(h)+':'
else:
    x+=str(h)+':'
if len(str(m))==1:
    x+='0'+str(m)
else:
    x+=str(m)
print(x)
