import sys
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines

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

def solve(a,b,c):
    if a == b == c == 0:
        return -1, []
    elif a == b == 0:
        return 0, []
    elif a == 0:
        return 1, [-c / b]
    D = b * b - 4 * a * c
    if D < 0:
        return 0, []
    elif D == 0:
        return 1, [-b / (a+a)]
    if b < 0:
        a,b,c = -a,-b,-c
    sqD = D ** .5
    alpha = (-b - sqD) / (a + a)
    prod = c / a
    beta = prod / alpha
    return 2, sorted([alpha, beta])

n, nums = solve(a,b,c)
if n == -1:
    print(-1)
else:
    print(n)
    print(*nums, sep='\n')