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.
time = input().split(":")
sleep = input().split(":")
hour = (int(time[0])-int(sleep[0]))%24
minute = int(time[1])-int(sleep[1])
if minute < 0:
	hour = (hour-1)%24
	minute %= 60
if hour < 10:
	hour = "0"+str(hour)
if minute < 10:
	minute = "0"+str(minute)
start = [hour,minute]
print(start[0]+":"+start[1])
				    	  		 		   			   		