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.
jam,menit=map(int,input().split(':'))
lamajam,lamamenit=map(int,input().split(':'))
a=jam-lamajam
b=menit-lamamenit
if b<0: a-=1
a=a%24
b=b%60
if a<10:
	a='0'+str(a)
if b<10:
	b='0'+str(b)
print(str(a)+':'+str(b))
	 	  	  		 			 						  			 	