from math import sqrt
if __name__ == "__main__":
    a, b, c = map(int,input().strip().split())
    s = set()
    if 2 * a == 0:
        print(-1)
    elif b ** 2 - 4 * a - c < 0:
        print(0)
    else:
        res_1 = (-b + sqrt(b ** 2 - 4 * a * c)) / (2 * a)
        res_2 = (-b - sqrt(b ** 2 - 4 * a * c)) / (2 * a)
        s.add(res_1)
        s.add(res_2)
        print(len(s))
        for i in s:
            print(("%0.10f" % i))