a,b,c = map(int,input().split())
D = b*b-4*a*c
if a==0:
    if b==0:
        print(0 if c else -1)
    else:
        print(-c/b)
elif D < 0:
    print(0)
elif D==0:
    print(1)
    print(-b/2/a)
else:
    print(2)
    if b < 0:
        a,b,c = -a,-b,-c
    r = -(b+D**0.5)/2/a
    s = c/a/r
    print(*sorted([r,s]),sep="\n")