def solve(a, b, c):
    if a == 0:
        if b == 0:
            if c == 0:
                return -1, []
            else:
                return 0, []
        else:
            return 1, [-c / b]
    else:
        D = b ** 2 - 4 * a * c
        if D > 0:
            return 2, [(-b - D ** (1 / 2)) / (2 * a), (-b + D ** (1 / 2)) / (2 * a)]
        elif D == 0:
            return 1, [-b / (2 * a)]
        else:
            return 0, []

N, X = solve(*map(int, input().split()))
print(N)
if N:
    print(*X, sep='\n')