Disqus Software Engineer interview questions

I applied by emailing a recruiter with my resume and cover letter. She replied asking me to complete a take-home coding challenge within 2 days. I submitted my solution and after another day I was asked to update it to improve the runtime of a specific case. I did so and submitted my updated solution promptly. I felt that my solution was very good, but about 2 weeks after that I was told that they were not moving forward with my application. I was never offered an interview.