from math import sqrt

a, b, c = map(int, input().split())
disc = b * b - 4 * a * c
if disc < 0:
    print(-1)
elif disc == 0:
    print(1)
    print(-b / 2 / a)
else:
    print(2)
    print((-b - sqrt(disc)) / 2 / a)
    print((-b + sqrt(disc)) / 2 / a)
