l=lambda:map(float,raw_input().split())
a,b,c=l()
if a==0:
    if b<>0:
        print 1
        print '%.10f' %(-c/b)
    else:
        if c==0:
            print -1
        else:
            print 0
    exit()
delt=b*b-4*a*c
if delt<0:
    print 0
elif delt>0:
    print 2
    print '%.10f' %((-b-delt**0.5)/(2*a))
    print '%.10f' %((-b+delt**0.5)/(2*a))
else:
    print 2
    print '%.10f' %(-b/(2*a))
    print '%.10f' %(-b/(2*a))