Blog ›My Position on the solved.ac Whitelist (5/8)

Hi, this is Suhyun Park, the operator of solved.ac. This isn't the official blog but my personal one, but since solved.ac doesn't really have a good place to post something like this, I decided to write it here.

solved.ac started its closed beta last July, and as of now it's been running for 10 months. Here's why I've been running the site as a whitelist-based closed beta:

1. In the early days of the site, very few problems had difficulty ratings (~2,000 contributions from Sogang University), and there was no proper standard for difficulty, so I wanted to shape a direction for a difficulty standard that many people could consider reasonable

2. Since Startlink doesn't officially allow scraping BOJ, I needed to keep the number of scraped users down in order for the site to keep existing

That said, I really hoped a lot of people would get into problem solving through this site, so with that in mind I left difficulty lookups open to everyone, even those not on the whitelist.

Later, as the integration with BOJ was decided, the impact of (2) shrank, so I slowly expanded the whitelist. Currently, 15,342 users are on the whitelist. Compared to 3,517 in August, right when the beta started, that's about a fivefold increase.

However, individual whitelisting had its side effects, so I stopped accepting individual whitelist applications in March. Here's why:

• People frequently copied other people's source code and submitted it to meet the tier requirement for individual whitelisting. Neither solved.ac nor BOJ allows this, and solved.ac removed such users from the whitelist as soon as cases were found.

• The load of scraping individually whitelisted users grew. The current structure of solved.ac is designed so that scraping group whitelists works much more efficiently.

Reports of malicious users copying and pasting source code increased, so I ended up handling requests I wouldn't have had to deal with if I hadn't created the individual whitelist in the first place, which took time away from developing other features, not just for me but for Startlink as well. I decided to stop accepting individual whitelist applications, judging that spending that time on the integration work or on new features would be far more beneficial to the users waiting for the integration.

Since then, I've received a lot of criticism and reproach from some BOJ users (mostly saying it's unfair), and after much thought, I've decided to stop accepting the group whitelist, which I'd kept open, after May 16. However, once the integration with BOJ is completed soon, everyone will be able to use the site regardless of the whitelist, so I kindly ask you to wait just a little longer.

Thank you.

Additionally, below are some frequently asked questions about the site and my answers to them.

What's good about the integration? – Once the integration is done, the beta ends. The whitelist goes away and anyone can log in. Right now each user and group has a fixed update interval, but after the integration I plan to make experience points reflect immediately as soon as you solve a problem.

What's your salary? / How much are you paid for this? – solved.ac is entirely my personal project, and I'm not receiving anything other than donations. That said, the operating costs are supported by Startlink.

Are there plans to provide an API? – There are plans, but it's not a high priority. The main reason is that I don't have enough time to write documentation. If you want to build something using solved.ac's content, rather than crawling the solved.ac site itself, please figure out the undocumented API endpoints by reverse engineering the plugin source code and use those.

My whitelist application was rejected / I was removed from the whitelist for copying source code. Can I use the site normally after the integration? – You'll be able to log in, but according to solved.ac's rules, your experience points will remain fixed at 0 for 65,535 days even after the integration.