from decimal import Decimal, getcontext
getcontext().prec = 50
a, b, c = map(Decimal, input().split())
if a == b == c == 0:
    print(-1)
elif a == b == 0:
    print(0)
elif a == 0:
    print(1)
    print(-c / b)
else:
    D = b ** 2 - 4 * a * c
    if D < 0:
        print(0)
    elif D == 0:
        print(1)
        print(-b / (2 * a))
    else:
        print(2)
        print((-b - D ** Decimal("0.5")) / (2 * a))
        print((-b + D ** Decimal("0.5")) / (2 * a))