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.
wakeup = input().split(":")
sleepTime = input().split(":")
wakeupHour = int(wakeup[0])
wakeupMinute = int(wakeup[1])
sleepHour = int(sleepTime[0])
sleepMinute = int(sleepTime[1])
answerHour = wakeupHour - sleepHour
answerMinute = wakeupMinute - sleepMinute
answerSeconds = 0
minTxt = ""
hourTxt = ""
if(answerMinute < 0):
    answerMinute += 60
    answerHour -= 1
if(answerHour < 0):
    answerHour += 24

if(answerMinute < 10):
    minTxt = "0" + str(answerMinute)
else:
    minTxt = answerMinute
if(answerHour < 10):
    hourTxt = "0" + str(answerHour)
else:
    hourTxt = answerHour
    
print(f"{hourTxt}:{minTxt}")