Hello Coders!
The October edition of 101 Hack is here. This time we have 5 interesting challenges lined up for you. The contest commences on 1st Nov 2014 at 06:30 UTC, and will run for 2 hours. You can sign up for the contest here.
The problem statements will be available in English, Russian and Chinese.
Top 10 on leaderboard get cool HackerRank T Shirts
Books for individual challenge-leaderboard toppers
Problem Setter
GaryYe
Please try all problems, Editorials will be available at the end of contest.
GL&HF
Update
Contest has started!
Very unusual starting time :O
Is it too early? We are experimenting with different timezones.
Time was OK for me, but just take a look at number of participants — it decreased from 400+ in September to 200+ in October. I think that unusual starting time was main reason for this.
Also i think that it is good idea to highlight unusual starting time in announcement or focus on it — i did not even pointed that contest starts so early, because i read it like i am usually reading problem statements — "ok, 101 Hack, this Saturday, 5 problems, 2 hours, like usual, t-shirts, let's take a look at problem setter, ok". I noticed that contest starts much earlier than usual only after reading comment of mmaxio.
I am not familiar with the website. Is it possible to have a look at the test cases when the contest is over?
If you made a submission to the problem go to submissions and next to each test case you'll see a button to download it.
Is there anyway to disable the editor on Hackerrank? Like not showing it at all, just the upload button.
is there any tutorial? If yes, please, give me a link. If no, how to solve C? what asymptotics is required? I had O(NlogH * 2K), but it got TLE.
Did you use segment tree? If you did, use Binary Index Tree instead. My friend got AC when used BIT. :)
Yes, i used segment tree. Okay, thank you!)
Actually your time complexity is OK. I guess the time limits were too strict and I'm sorry for that. The tutorial will be published after I finished describing the last two problems.
Edit: You will see the tutorial of each individual problem in an extra tab.
Edit2: Editorials updated :-) C has actually an O(n) memory complexity solution. Maybe you want to check it out. To be honest, the editorials aren't perfect, they should give you the right direction to solve the problems, but if you have any questions, just ask me.
Yeah, the time limit was a bit too strict in C. I got TLE with a BIT, just because I didn't cut down on the use of modulos. But considering how big the constant difference between BITs and segtrees is, there was probably no way to set the TL so that segtrees would pass.