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.
curr = input()
slept = input()

hc, mc = int(curr.split(":")[0]), int(curr.split(":")[1])
hs, ms = int(slept.split(":")[0]), int(slept.split(":")[1])

if hc == 0: hc = 24
if hs == 0: hs = 24

h = hc-hs
m = mc-ms

print('{:02d}'.format(h)+":"+'{:02d}'.format(m))
