a, b, c = map(int, input().split())
if a != 0:
    D = b**2-4*a*c
    if D > 0:
        print(2)
        print((-b-D**0.5)/(2*a))
        print((-b+D**0.5)/(2*a))
    elif D == 0:
        print(1)
        print((-b)/(2*a))
    else:
        print(0)
else:
    if b != 0:
        print(1)
        print(-c/b)
    else:
        if c == 0:
            print(-1)
        else:
            print(0)