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 = 0
answerMinute = 0
answerSeconds = 0
wakeupSeconds = (wakeupHour * 60 * 60) + (wakeupMinute * 60)
sleepSeconds = (sleepHour * 60 * 60) + (sleepMinute * 60)
minTxt = ""
hourTxt = ""
if(wakeupSeconds < sleepSeconds):
    wakeupSeconds = (24 * 60 * 60) + (wakeupMinute * 60)
   
answerSeconds = wakeupSeconds - sleepSeconds
answerHour = int(answerSeconds / 3600)
tempMin = 0
if(answerHour <= 0):
    tempMin = int(answerSeconds / 60)
else:
    tSec = answerSeconds - (answerHour * 60 * 60)
    tempMin = int((tSec / 60))
if(tempMin < 10):
    minTxt = "0" + str(tempMin)
else:
    minTxt = tempMin
if(answerHour < 10):
    hourTxt = "0" + str(answerHour)
else:
    hourTxt = answerHour
    
print(f"{hourTxt}:{minTxt}")