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.
import string
wu = input()
t = input()
a = wu.split(':')
b = t.split(':')
resHr = int(a[0]) - int(b[0])
resMin = int(a[1]) - int(b[1])
if int(resHr) < 0:
	resHr = str(resHr % 24)
else:
	resHr = str(resHr)
if int(resHr) < 10:
	resHr = '0'+str(resHr)
if int(resMin) < 10:
	resMin = '0'+str(resMin)
else:
	resMin = str(resMin)
if int(resMin) < 0:
	resMin = str(x % 60)
	resHr = str(int(resHr) - 1)
else:
	resMin = str(resMin)			
print(resHr+':'+resMin)


		  				 		 		 	   			 	    	