from decimal import Decimal

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

def quadroot(a, b, c):
    bruh = []
    negb = -1*b
    discriminant = (b**2 - 4*a*c)**(1/2)
    bottom = 2*a
    bruh.append(format((negb - discriminant) / (bottom), ".7f"))
    bruh.append(format((negb + discriminant) / (bottom), ".7f"))
    return bruh

if a == 0 and b == 0 and c == 0:
    print(-1)
    exit()
if a == b and b == 0 and c != 0 or (b**2 - 4*a*c) < 0:
    print(0)
    exit()
ans = []
if a == 0:
    ans.append((-1*c) / b)
else:
    ans = quadroot(a, b, c)

ans1 = sorted(list(set(ans)))
print(len(ans1))
print('\n'.join([str(bruhh) for bruhh in ans1]))