a,b,c=map(int,input().split())
D=b*b-4*a*c
if a == 0:
    if b == 0:
        print(-1 if c==0 else 0)
    else:
        print(1,-c/b,sep='\n')
else:
    if D==0:
        print(1,-b/a/2,sep='\n')
    elif D<0:
        print(0)
    else:
        if b<0:
            a,b,c=-a,-b,-c
        p=(-b-D**(0.5))/2/a
        q=c/a/p
        if p>q:p,q=q,p
        print(2,p,q,sep='\n')