from math import sqrt

x = input()

y = x.split()

a = int(y[0])
b = int(y[1])
c = int(y[2])

det = b**2-4*a*c

if a ==0:
    print(-c/b) if b !=0 else print(-1)
    
if b==0:
    if a*c<0:
        print(2)
        print(-sqrt(-c/a))
        print(sqrt(-c/a))

if det <0:
    print(0)

if det ==0:
    if a==0 and b==0 and c==0:
        print (-1)
    else:    
       print(1)
       print(-b/2*a)
    
if det>0:
    print(2)
    print("{0:5f}".format((-b-sqrt(det))/2*a))
    print("{0:5f}".format((-b+sqrt(det))/2*a))
