a,b,c=map(int,input().split()) if a==0 and b==0 and c==0: print(-1) elif a==0 and b==0: print(0) elif a==0: print(1) print(-c/b) else: tmp0=-4*c*a+b**2 tmp=-c+b**2/(4*a) tmp/=a if tmp0<0: print(0) elif tmp0==0: print(1) print(-b/(2*a)) else: import math tmp=math.sqrt(tmp) print(2) print(-tmp-b/(2*a)) print(tmp-b/(2*a))