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.
wake = input()
sleep = input() 
hours_wake = int(wake.split(":")[0]) 
min_wake =  int(wake.split(":")[1]) 
hours_sleep = int(sleep.split(':')[0])
min_sleep = int (sleep.split(":")[1]) 
if hours_wake == 0 : 
    hours_wake = 24 
if hours_sleep == 0  :
    hours_sleep = 24 
res_min = abs(min_sleep - min_wake) 
res_hours = abs(hours_sleep -hours_wake)
print(str(res_hours).zfill(2) + ":" + str(res_min).zfill(2))