import numpy as np
a,b,c=map(int,input().split())
if a==b==0:
  if c:
    print(0)
  else:
    print(-1)
elif a==0:
  x=sorted(set(np.roots([b,c])))
  for i in range(len(x)-1,-1,-1):
    if str(type(x[i]))!="<class 'numpy.float64'>":
      x[i]=x[i].real
  x=sorted(set(x))
  print(len(x))
  if len(x):
    print(*x,sep='\n')
else:
  x=sorted(set(np.roots([a,b,c])))
  if b*b<4*a*c:
    print(0)
    exit()
  for i in range(len(x)-1,-1,-1):
    if str(type(x[i]))!="<class 'numpy.float64'>":
      x[i]=x[i].real
  x=sorted(set(x))
  print(len(x))
  if len(x):
    print(*x,sep='\n')