a, b = [input(), input()]
c = int(a[0:2]) * 3600 + int(a[3:5]) * 60 + int(a[6:8])
d = int(b[0:2]) * 3600 + int(b[3:5]) * 60 + int(b[6:8])
e = d - c
if e <= 0:
    e += 86400
print(
    f"{'{0:02d}'.format(e // 3600)}:{'{0:02d}'.format(e % 3600 // 60)}:{'{0:02d}'.format(e % 60)}"
    )

b702f578accb228b1d8da915527cc75e070d4cec
<mask token>

<mask token>
if e <= 0:
    e += 86400
print(
    f"{'{0:02d}'.format(e // 3600)}:{'{0:02d}'.format(e % 3600 // 60)}:{'{0:02d}'.format(e % 60)}"
    )

a, b = [input(), input()]
c = int(a[0:2]) * 3600 + int(a[3:5]) * 60 + int(a[6:8])
d = int(b[0:2]) * 3600 + int(b[3:5]) * 60 + int(b[6:8])
e = d - c
if e <= 0:
    e += 86400
print(
    f"{'{0:02d}'.format(e // 3600)}:{'{0:02d}'.format(e % 3600 // 60)}:{'{0:02d}'.format(e % 60)}"
    )
