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.
a,b=map(int,input().split(":"))
c,d=map(int,input().split(":"))
if a==c:
    if len(str(b-d))==1:print("00"+":"+"0"+str(b-d))
    else:print("00"+":"+str(b-d))
else:
    if a==00:a=24
    if c==00:c=24
    if len(str(a-c))==1:
        if len(str(b-d))==1:
            print("0"+str(a-c)+":"+"0"+str(b-d))
        else:print("0"+str(a-c)+":"+str(b-d))
    else:
        if len(str(b-d))==1:
            print(str(a-c)+":"+"0"+str(b-d))
        else:print(str(a-c)+":"+str(b-d))
