def main():
    import sys
    from math import sqrt
    input = sys.stdin.readline

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

    if a == b == c == 0:
        print(-1)
        exit()
    if a == b == 0:
        print(0)
        exit()
    if a == 0:
        print(0)
        print(-c / b)
    D = b**2 - 4*a*c
    if D > 0:
        print(2)
        print((-b-sqrt(D)) / (2*a))
        print((-b+sqrt(D)) / (2*a))
    elif D == 0:
        print(1)
        print(-b/(2*a))
    else:
        print(0)


if __name__ == '__main__':
    main()