Attention Coders!
Gear up for the Competitive Programming Contest of NITS HACKS 7.0, brought to you by the Coding Club of NIT Silchar, in association with the grand Tecnoesis festival at NIT Silchar! Dive into the excitement of team-based coding challenges and vie for fantastic prizes!
Who Can Join? Everyone is welcome to participate in the contest! However, only undergraduate students enrolled in Bachelor’s or Dual Degree programs in India are eligible to receive prizes.
Contest Format:
The contest will follow ICPC guidelines.
Preliminary Round: Open to all teams—show us your skills!
Final Round: A total of $$$30$$$ teams from prelims will compete for glory, with $$$10$$$ reserved spots exclusively for NIT Silchar teams (excluding the top 20).
If you’re ready to take on the challenge, join us for a coding showdown. Don’t miss this chance to prove yourself among the best!
Rules:
A team of 2-3 members from the same college is required to participate in the contest.
An eligible individual may join only one team.
Each participant must have a Codeforces account.
A team must be created in Codeforces composed of the members.
Finally, you should register for the contest using the formed team.
The team must also register through the link below; not adhering to this requirement will make the team ineligible for winning prizes.
Contest Time:
The preliminary round will be on [contest_time:563188] and will last 3 hours (online).
The final round will be held on [contest_time:564294] (Updated) and will last 3 hours (online).
Click on the link below to take part in the contest. Registration for the contest will start 6 hours before the contest.
The problems are authored by sroid_03, Amartya3, rainb0ySimp, sohailkazi, and me (GetRekt).
We would like to thank :
awoo, EyadBT, AyuAnchor, manikiran949, and LikithReddy123 for their valuable testing, review and feedback.
MikeMirzayanov for the amazing Codeforces and Polygon platforms.
See You on the leaderboard!
UPD 1: There will be 7 — 9 problems. There can be at most 69 interactive problems, so we suggest you go through this guide.
UPD 2: Registration has begun.
UPD 3:
The finals have been postponed to [contest_time:564294].
The problems may not be sorted according to difficulty.
Excited!!
looking forward to it
Very excited for this!
Absolutely buzzing!
curious!!
the finals are in online mode or offline?
Both rounds are online.
too much excited!!!
How many questions are to be expected this time??
There will be 7 — 9 problems.
Excited !!
Excited!!!
LESSSGOOOOOO!!
LooKing Forward....
Me tooo
Cant wait !!
How many questions will be their in each contest?
Both rounds will have around 7 to 9 problems.
Too much excited...
What measures are there in place to thwart Chat GPT solutions, both rounds are online people will test their GPT juice for sure.
We have tested all problems on ChatGPT o1-preview. AI should hopefully have next to no effect on the participants skilled enough to qualify / win.
Let's Gooo
Looking forward!
Excited!!
Hey the registration link is not working, can you please check? @GetRekt
Can you please check again and let us know what issue / error you have been facing? The form seems to be working fine from our end, and we're receiving valid form submissions from participants.
The bit.ly link is not working for me (site can’t be reached) , but i went on the official webiste found goolge form link there, which worked.
I have replaced the bit.ly links with the original ones. Can you please check now?
Excited, btw can a team not qualified for final round also give that contest, just unrated or something?
A mirror contest will be held.
great!!!
What is the prize distribution? only for 1st ranker or like for top3 or for top5??
Can I get previous years hacks problems?
Can't Wait!!!!
Could you please provide the link of previous contests?
how to practice? Any resources...
Hope this helps those looking for older problems.
Excited for the contest!!
is the difficulty rating in random order or in sorted order?
The problems may NOT necessarily be sorted in order of difficulty. Participants are therefore advised to read all problems.
Wow!!!! Very excited
excited !!
Are there prizes for preliminary round?
Prizes are for the final round.
Team USS_Coders is readyyyy :)
As a Tester , I tested my first contest , and all the questions are amazing, All the best to all the participants .
Excited
What is the deadline to fill the g-form ?
Anytime before the prelims ends.
Hope to solve all 69 😏
while registering i mistakely register as individual. Now how to register as Team.
Click on Registered participants (the number you see) , then click on Unregister , and again register as Team
Why do i get wrong answer on test 2 in E and H . I don't get it. Is there a problem with the testcases?
Is this happening with everyone?
There is a very clever O(1) solution for E. The key idea is observing that the answer can't exceed two, because if the endpoints are not equal then one of it is obviously 0. Applying two right shift and one left shift (OR VICE VERSA) will make the zeroes equal, However, the answer can be 1 also when there is two consecutive zeroes at end points. Here is my solution for reference -> [submission:290426855]
Excited!!
How to do D $$$??$$$
I am trying to make a graph with edges as possible transition to left and right (including ground). Then I am using a modified dijkstra from ground to find the answer vector. But I am stuck in how to find the left and right nodes?
Process platforms in increasing order of heights. For each platform assume we have dp for the platforms at height lower than it. For both the endpoints find the platform on which the ball might land on. To do this I used segment tree with coordinate compression.
I was thinking in the same direction, can you please explain how to do the last part, "to find the platform the ball might land on using segment tree and coordinate compression"
Note that what matters is only points in increasing order and not their exact sizes. Since we have $$$n$$$ segments, there are atmost $$$2n$$$ distinct points. So we give each of the points in increasing order a new value which signifies its relative position and not exact one. This is the main essence of coordinate compression. Now assume that when we process $$$i^{th}$$$ platform (in increasing order of their heights), we have the information of which segments in the initial $$$1$$$ to $$$i - 1$$$ contains any specific point. For the two endpoints of this segment, find the required values and then update the new information, ie $$$l_i$$$ $$$\rightarrow$$$ $$$l_i$$$ + $$$len_i$$$ is contained in $$$i^{th}$$$ segment. All this can be easily done using a segment tree (as we now have atmax $$$2n$$$ nodes). You can look at my submission if it is visible to you Submission
Okk, understood after dry running your submission. Thank you for the explanation , learnt something new!
rock it guys
There is something wrong with D. Some times my code passes till 93rd test case and sometimes till 64th test case. The exact same code. Can someone explain why?
because the organisers dont know how to properly set testcases.
It's because your code is barely fast enough to pass the 63th testcase. Due to variations in judging, sometimes your code goes above the 2000ms limit for the 63th tc and TLEs, and other times it just passes under the time limit.
Try optimizing your code. We've opened all the submissions to other codes, you view some of the other accepted codes for reference.
64 to 93 to 27 is unusually high variation. Never seen such inconsistency in any problems before this. Also as the other guy has pointed out there are too many n = 2e5 test cases. For problems in standard contests test cases with max value of n are just a small fraction. Could that be the reason?
D has so many pointless bot generated large testcases that gives tle for nlogn solutions.
Edit : Mass downvoting without explaining anything is not gonna make you guys look better. Put some effort in setting sensible test-cases next time.
What are the prizes
Can you clarify whether the prizes are for top 10 or top 3
D can also be solved without segment tree. Just form a DAG, with every platform as node and edges from platform x -> y, if ball can fall directly from x to y.
290435436