a,b,c = map(int,raw_input().split())
if a==0 and b==0 and c==0:
    print -1
elif a==0 and b==0 and c<>0:
    print 0
elif a==0 and b<>0:
    print 1
    print '%8f'%(-1.0*c/b)
elif a<>0:
    delta = b*b-4*a*c
    if delta <0:
        print 0
    elif delta==0:
        print 1
        print '%8f'%(-1.0*b/(2*a))
    else:
        print 2
        print '%8f' % ((-1.0 * b - delta**0.5) / (2 * a))
        print '%8f' % ((-1.0 * b + delta**0.5) / (2 * a))
