a,b,S = input().split()
a = int(a)
b = int(b)
S = S[3:]
if "." not in S:
    c = S[0]
    d = int(S[1:])
    if c=="+":
        delta = d-9
        a += delta
    else:
        delta = 9+d
        a -= delta
    a = a%24
else:
    c = S[0]
    f = float(S[1:])
    if c=="+":
        if f>=9:
            d = int(f)
            e = f-d
            delta = d-9
            a += delta
            b += int(e*60)
            if b>=60:
                a += 1
                b -= 60
        else:
            delta = 9-f
            e = delta-int(delta)
            delta = int(delta)
            a -= delta
            b -= int(e*60)
            if b<0:
                a -= 1
                b += 60
    else:
        delta = 9+f
        e = delta-int(delta)
        delta = int(delta)
        a -= delta
        b -= int(e*60)
        if b<0:
            a -= 1
            b += 60
    a = a%24
print(f"{a:02d}:{b:02d}")