from math import sqrt
import sys

a, b, c = map(float, input().split())

e = 0.0000001
D = b ** 2 - 4 * a * c

if a == 0 and b == 0 and c == 0:
    print(-1)
elif a == 0 and b != 0:
    print(1, -c / b)
elif a != 0:
    if D > 0 :
        print(2,(-b + sqrt(D)) / (2 * a), (-b - sqrt(D))/(2 * a))
    elif abs(D) < e :
        print(1,(-b + sqrt(D)) / (2 * a))
    elif D < 0:
        print(0)
else:
    print(0)