Hi. I’ve recently changed the link structure of the website, which might have landed you here.
Here’s what you can do.
1) If you reached here looking for a problem, use the url: doubleroot.in/problems/problem-n, where n is the problem number mentioned in the linked you clicked. Else you can head over to the problems page.
2) If you came here looking for a lesson, go to the lessons page. I’ve organised the lessons in a much improved manner.
3) For any other issues, you may drop a message at the Facebook page. I’ll be happy to help you out !
Thanks for visiting and happy learning !