#yuki955
import math
import sys

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

if a==0 and b==0 and c==0:
 print(-1)
 sys.exit()
if a==0 and b==0:
 print(0)
 sys.exit()
if a==0:
 print(1)
 print(-c/b)
 sys.exit()

D=b**2-4*a*c
if D<0:
 print(0)
 sys.exit()
if D==0:
 print(1)
 print(-b/(2*a))
 sys.exit()

print(2)
if b<0:
 a,b,c=-a,-b,-c
x1=(-b-math.sqrt(D))/(2*a)
x2=(b**2-D)/(2*a)/(-b-math.sqrt(D))
if a>0:
 print(x1)
 print(x2)
else:
 print(x2)
 print(x1)