With a New Year, come many things “New.” You have aspirations, expectations, and resolutions for the year ahead. Determined and focused you are ready to take on the world. It goes for the programming fanatics as well. For programmers looking to solidify their strengths and make a mark on the programming world, it was the beginning of a fresh programming calendar packed with many exciting programming contests to take part in and win. The first in line was our January Challenge 2017, set on the first Friday of 2017.
While the aspiring participants waited for the contest to start, we gave them a little New Year surprise, to sweeten the start of the year for them. However, like all sweet things, they were required to work a tad harder for their sweet. And they did work for it. How well, though, we will find out in this look back at the first long challenge of the year.
The January Challenge 2017 was coming on close heels of the busy ACM ICPC 2016 – 2017 India regionals. We along with many other ACM ICPC aspirants and some members of our problem setting panel were on the constant move to different regionals across India. And after experiencing the live action at the onsite contests, it was time to experience the same with global participants online.
The course for January Challenge 2017 came from Maksym Bevza, Praveen Dhinwa, Misha Chorniy, Vaibhav Tulsyan, Sidhant Bansal Sergey Nagin, Kevin Atienza, and Satyaki Upadhyay in company with the Istvan Nagi, making a comeback in the role of tester. Alongside them were our translators in Sergey Kulik (Russian), Team VNOI (Vietnamese) & Hu Zecong (Mandarin) and our editorialist Vaibhav Tulsyan. We thank them all for their efforts that they put all through the holiday season to get the contest ready. Like always, with them by our side, we were expectant of a great contest. And even though, not all the problems were served at ones, the participants seemed to enjoy all of them as and when they were served during the course of the contest.
The first AC submission of the year 2017 in our monthly contests came from poikniok on CAPIMOVE, who took 13 minutes to get past the problem, the first in the contest was by slowrunner on CHEFCIRC, but it was a WA. And with that, the tone was set for the contest. As most of the early joiners went for CAPIMOVE, which was the first to be solved, there were few others who went for CHEFCIRC and CATSDOGS, but not many got the result they were looking for. The aforementioned three problems gave a smooth start to many users’ first challenge of the year, while for very few it became a source of frustration too. But that’s how the nature of every programming contest is, you win some, you lose some.
We won’t put it on the New Years Eve hangover, but the slow flow of the submissions into the contest gave it away that not many had put their party hats back in the closet. The first 50 submissions into the contest took 40 minutes. The next 50 took another 40. So, in the first hour of the contest, we barely received a tad over 100 submissions, but that didn’t ring any alarms as we were expecting it to be a slow start for the contest and are sure of it to pick up pace as the contest progresses. And that’s exactly what happened.
The contest started with 4 problems to start with and the early birds seemed to be enjoying them, with Capital Movement, Reservior, and Cats and Dogs being the early favorites. As we moved into the contest, the submissions started spreading onto the other problems as well. And with that, the race to the top was on as well. While the submissions table kept getting populated with submissions of different result code, the rank table was still missing some of its familiar names. But the January Challenge 2017 perhaps was not for the familiar names after all. Yes, there were few in ceilks, ccz181078, hellkitsune, rajat1603, skyfire and others, but it wasn’t about them, this time.
The January Challenge 2017 belonged to the comparatively new and unfamiliar names. If truth be told, 4 out of the top 5 names on the rank table are adolescents on CodeChef, with 5 or less contests under their belt. However, that did not have any impact on their performance and approach towards the contest. jobasha, mirosuaf, and swm_sxt seemed unmoved by the reputations of the names accompanying them on the rank table and kept going calmly about their business. And even though they were eventually triumphed by ceilks and ccz181078 for the first two slots, they did secure positions in the top five of the first Long Contest of the year.
And now, let us meet all the names featuring on the rank table:
We start with the women:
The ROW top 10:
The Indian top 20:
The Indian top 5 school students:
The ROW top 5 school students:
Now, for the special achievers, we head towards the top Challenge Problem solvers.
First the top 3 from ROW, other than the winners:
Now, the Indian top 3:
Give it up for all our winners!
We hope you all enjoyed the contest and its content all through the ten days of the contest. However, if you faced even the slightest of problems, we have the editorials for all the problems waiting for you. So, head over to the link below and munch on the editorials for January Challenge 2017.
With that, it’s safe to say that the January Challenge 2017 announced the arrival of many promising names on the rank table and we look forward to getting many such promising performances from them in coming years. Who impressed you the most or who are you looking forward to in the year ahead, do let us know in the comment section? Also, if your favorites are not on the rank table, do let us know of that as well and we will keep a close eye on them.
Now, it’s time to say goodbye and move towards the shorter format of our contests in January Cook-Off 2017 and January LunchTime 2017. We will come back soon with their stories.
Till next time, bye.
See you at the contests!
When you have a big day tomorrow, you tend to calm down, relax, and just prepare your mind for it. It holds true for many big sportsperson, many big movie stars, and pretty much everyone, except for programmers. Programmers are the most restless creatures on the night before. And after being with, knowing, and interacting with so many programmers over the years, we certainly can assert that. It was not different the night before the first ACM ICPC 2016 India regional was scheduled to take place at Hindustan University. Knowing that most of the top programmers in the country will either be travelling for the onsite event, or will be relaxing at home to compete in the coming ones, we thought it’s an ideal situation for a newcomer to rise and shine. And we could not have been far from the truth.
That he is talented and perhaps an emerging legend in the Indian programming world is something we have been hearing about rajat1603. Time and again, he even has proved it in various competitions. From being among the top school teams to come for the SnackDown 2015 Onsite to being one of the few school students to have secured a place in top 5 in our Cook-Offs, he has proven his mettle time and again. And the December Cook-Off 2016 was yet another display of his sheer brilliance. This time though, the setup had changed a tad.
He no longer is a school student, he was competing in his very first ACM ICPC Regional, and just like himself, his counterparts in uwi, yenthanh132, biginnnner, and many others had evolved too. And considering all that, we thought a night before his first ACM ICPC regional he might want to catch a breather and focus his energy on the big day tomorrow. He, on the other hand, had totally different plans. The December Cook-Off 2016 started sharply at 09:30 pm on 18th December 2016 and in the very first minute, CHEFSETC was cracked by, you guessed it, rajat1603. One minute is all it took him to crack the first problem of our Cook-Off. If that doesn’t send strong signals to your counterparts, we don’t know what does. And with that, it was on.
Contrary to the blistering start from Rajat, uwi had a slippery start when he got TLE in his first submission on CHEFINS. However, he was quick to recover and bagged his first AC inside the first 8 minutes of the contest as he cracked CHEFSETC. If truth be told, CHEFSETC was almost solved by everyone who attempted it. Off the first 100 submissions into the contest, 98 were on CHEFSETC, and that made it obvious that it was the easiest problem in the contest. However, getting the easy problem quickly doesn’t win you the Cook-Off. So, it was better for the participants to move on to the other problems as soon as they can, and they did.
Rajat grabbed his second in CHEFARRB in the 8th minute of the contest, while uwi took further 10 minutes to crack the same. By this time, the competition was nicely balanced. But then, uwi decided to revisit CHEFINS, however, nothing changed this time as well, TLE is what he got this time as well. By this time, Rajat had already cracked CHEFNUMK and got a significant lead over uwi. With 3 problems to his name inside the first 45 minutes of the contest, Rajat seemed comfortably cruising to the top. However, CHEFINS was not easy for him either. It took him more than half an hour to get it right. That’s pretty much the time he needed to crack the first three problems of the contest. But once he got that, with no penalty to his name, it pretty much sealed the deal for him. And a top slot for him into the contest was almost assured, however, there still was a problem unsolved, yet no one had attempted it and with uwi struggling CHEFINS it was highly unlikely that he was going to attempt that one. So we sat back and waited for the final bell to ring and find out whether 4 out of 4 ACs can get Rajat a Cook-Off win, and turns out they could.
With that Rajat had sent a strong signal to all his counterparts competing with him at the ACM ICPC regionals. And he didn’t disappoint at the regionals either. If you were following our ACM ICPC live coverage, you would know what we are talking about. For now, let us quickly take you to the rank table for December Cook-Off 2016 and see who stood where.
We start with the Global top 10:
Now, the Indian top 10:
Let’s give it up for all our winners and for all you wonderful people on your performances in the contest.
The fifth problem from COOK77 i.e. CHEFTRI4 remained solved during the contest, which makes the editorials of the contest even more important. So, if you are still wondering around CHEFTRI4, check out the editorials for the contest below and get over it.
And that completes the tale of the December Cook-Off 2016. We hope you enjoyed the contest and its tale. If you have any interesting insight, story, or any event that made COOK77 memorable for you, kindly do share it with us.
With that, there remains only 1 final story from our contests in the year 2016, that is the December LunchTime 2016 and we will publish that too very soon. Till then, keep watching this space, keep sharing the stories you like and do let us know what you think of our contests and their stories.
That will be all for now from everyone here at CodeChef.
Till next time, adios.
December is a busy month for every programmer around the world, for it is the ACM ICPC season. The regionals take place across the globe and the crème de la crème of the programming world battle it out to secure a coveted place at the ACM ICPC World Finals. It was no different this year as well. As we stepped into December, some of the regionals across the world had just concluded and we were just weeks away from the ACM ICPC Indian regionals.
With everyone looking for means to put the finishing touches to their ACM ICPC preparations, our December Challenge 2016, was their final big chance to test the waters, before they move towards the final frontier. While, for everyone else, it was the final chance to spend some time with their beloved computers and keyboards, before they step into the festive season and treat themselves with the sugary goodness that every festive season brings with it. It was an interesting setup. So, let’s see how the December Challenge 2016 fared.
The start to the contest was akin to pretty much like any other long contest we have had all through the year. It took saurabhrathi12 only 6 minutes to get the first AC of the contest on ANKTRAIN; it was followed by a couple of more ACs on the same problem. The second problem that saw an AC was SEAINCR, soon after ANKTRAIN. It remained like this for quite some time. The number of participation kept going up in the first half of the contest, while it stagnated in the latter half. And that is when the positions on the rank tables get decided. And it was an interesting looking rank table this time around. And we will tell you why.
When in the final days of the contest, the rank tables are generally occupied by the favorites. It was no different this time, the likes of sumeet_varma, rajat1603, mugurelionut, notimesea and many others still shining brightly on the rank tables. However, what was striking this time was the number of consistent performers, occupying the top slots. It’s one of those moments when you see your hard-work finally paying off. And the feeling certainly cannot be described in words. To see the likes of gvaibhav21, jtnydv25, ccz181078, come through the ranks and stamp their authority on the top slots of the rank table.
It was not easy to reach there and it certainly was not going to easy to stay there, especially when the seasoned campaigners have you in their sight. Every submission made now will decide their fate and position into the contest. But it seems that after years of wondering through the rank tables, they had mastered the art of defending their position on the rank table. So, as the fabulists would have it, it was a contest when persistence and grit won over experience. And now, we take a quick tour of the rank tables to meet all the winners from December Challenge 2016.
We start with the girls *Big round of applause*:
Now, on to the ROW top 10:
Now, the Indian top 20:
Now, let us move towards the schools to meet the young geniuses:
We start with the ROW top 5 from schools:
Now, the Indian top 5 from schools:
Now, for the special achievers, the top three scorers of the challenge problem, outside the winners:
First, the ROW top 3:
And finally, the Indian top 3:
Kudos to everyone on their brilliant performance in the contest!
With that, there are two more stories to tell from the month of December, which we will be updating pretty soon. We hope you had a wonderful 2016 and will have an even better 2017. And on that note, we would like to draw curtains on this delayed tale of December Challenge 2016. We hope you enjoyed the tale as much as you enjoyed the contest. If you have any feedback or words to say about the contest, the post, or CodeChef in general, you can always write to us at: firstname.lastname@example.org
Till next time, take care.
Even though we are here in Mumbai a rather tropical part of India with very little to minimum winters, somehow, this final part of the year makes us lazy. As a result we fall behind on putting up some important post contest blogs, not many, but few. And the year 2016 has been no exception. So, we would like to apologize for the missed blog posts and will try to publish all the missing ones, before taking on the posts for year 2017.
These posts will be a tad concise, so if you think we have missed any important event or something worth mentioning, do let us know in the comments section.
We start with the final contest of November, the November LunchTime 2016. With an all Indian problem setting and testing panel featuring Praveen Dhinwa and Animesh Fatehpuria, the November LunchTime 2016 promised some beautiful and delectable problems. And the participants comprehended that, as soon as the contest started.
We knew that the students are coming out of a big festive seasons and are staring at another big one too. What we didn’t know was that, the festive season had hardly made them any lethargic. The contest started at 7:30 pm IST and we got our first AC at 7:33 pm IST on CHEFSTUD. And it was soon followed by a flurry of AC on CHEFSTUD and few more on CHEFSSET. The plethora of ACs against the two aforementioned problems made the difficulty level of the problems rather apparent. So, the flow of submissions was almost in their direction only, with every now and then, someone trying their hand on the other two.
And while CHEFSTUD & CHEFSSET brought the initial smiles for the participants, it were TOMJERGA and BALANPOL, which seemed like the deciding factor for who stands where on the rank table. So, let’s head over the rank list and meet the top 20 schools students from our November LunchTime 2016.
We start with the ROW top 10:
Now, the Indian top 10:
A big round of applause for everyone on the rank table and for everyone who participated in the contest! You all did well.
For those looking to have a better look at the solutions of the problems from our November LunchTime 2016, we have the editorials waiting for you. So, head over to the link below and let the nom begin.
And with that, it’s time to put the pen down on this curtailed tail of November LunchTime and quickly move towards the pending stories of December. So, that will be all from us folks. We will come back soon, with three more exciting stories from our December contests.
Till then, keep coding and if you have any queries or feedback, shoot them our way at: email@example.com.
You all must be well aware about the Goodies site and our own, Laddus, that we launched when CodeChef turned seven. The objective behind our initiative towards this sweet project was to motivate our users to perform better and that too consistently so that they earn and accumulate more laddus. You can redeem these Laddus for the goodies that we have listed on our site.
Motivation persists only when a person finds her goal achievable. We have been continuously analysing our user activity on the Goodies site of their behaviour and what goodies they redeemed with their Laddus. Apart from our most popular goodies, the funky bottle, the cool bag, the classic CodeChef t-shirt and the elegant pen, we found very few users redeeming the Hard Disk Drive which made us take the decision of reducing its price.
Here is the good news for the readers who read this post till this point. The new price of Hard Disk Drive is 3500 Laddus. Just grab your laptop and start coding, collect more Laddus and get the HDD. We just made it easier for you, 30% easier. We know we are being too generous. You can thank us by performing better in the contests and we will be happier to see more users redeem the hard disk drive.
So what are you all waiting for? The Long Challenge contest is coming. Sharpen your skills, prepare your templates and get ready for the battle. See you on the leaderboard.
There still was a week to go for Diwali, but the celebrations had already begun here at CodeChef headquarters. And rightfully so, after all, we were hosting ACM-ICPC India Regionals, Online Preliminary Round 2016 on Saturday, 22nd October, 2016, followed by the October Mega Cook-Off 2016 on Sunday, 23rd October, 2016. We were thrilled, and if truth be told, a tad nervous too. Both of the contests had huge significance for different reasons and we wanted to get it right. So, with jittery eyes and a lot of butterflies in our stomach, we welcomed perhaps the most action-packed weekend of the year for us. And we could not be happier to say that, it just made our festive season even sweeter. You know it; you were there, weren’t you?
While, the ACM-ICPC India Regionals, Online Preliminary Round 2016 was an exciting tale on its own, we are here to tell you the story of October Mega Cook-Off 2016, which was pretty interesting on its own. Set by Lalit Kundu & tested by Kamil Debowski, the October Mega Cook-Off 2016 had a perfect blend of festive sweetness & thrill, which seemed to be the flavor of the season. The problem set based on the adventures of Serlock Holmes& Dr. Watson made them even more intriguing. And as the contest started, he participants grabbed their detective hats and were ready for the adventure.
The first mystery the users cracked was “Watson asks Does Permutation Exist”, which didn’t trouble the users much and was solved under 2 mins by rohanrtiwari. Rohan was then followed by many others and except for a couple of instances, most of them got it right in the first attempt only. And with that our COOK75 was off to a smooth start. While Watson asks Does Permutation Exist, was everyone’s first choice, because of the constantly increased AC submissions on it, we also had few submissions here and there on problems BOOKCHEF, UGLYF, COUNTWAY, and SWINDOW too, however, not many of them were AC though. And slowly it became even clearer that these problems are going to decide the fate and the winner of the contest. So, we waited and watched.
On the rank table, it was a Japanese domination with anta0, natsugiri, and uwi occupying 3 of the top 5 slots. And while we had the feeling that one of these three will take home the COOK75, we could not write off the likes of chemthan, biginnnner, and sumeet_varma before the contest ended. It all made the final minutes of the contest even more interesting. And to tell you the final outcome of the contest and to announce the winners, let us take you to the rank table:
We start with the ROW top 10:
Now, the Indian top 10:
A big round of applause for all our winners and for everyone who joined in the contest! We hope you enjoyed the contest and had a wonderful Diwali.
Now, for the final segment of the post, let us take you to the editorials for the October Cook-Off 2016. Penned by the problem setter, Lalit himself these editorials will give you the exact approach that the problem setter would have applied towards each of the problems. Even if you have gone through them, it would be good to have a look at them once more. So, here they are for you:
And with that, it’s time to say farewell. As the winter takes over, it’s time to wrap yourself in your cozy blanket, grab your cuppa hot coffee, and enjoy some sizzling programming contest. So, you take care of the former two and we take care of the final one.
Till next time, adios.
See you at the contest.
Nothing pleases us more than making learning to program fun for you. One such opportunity came our way when we met Vinit at the ACM-ICPC World Finals in Phuket, Thailand. Vinit Shah had given a passionate presentation of his platform called uDebug, which was an unknown entity to us until then.
We instantly liked uDebug as we had been wanting to provide something similar to our users but were unable to take it up. One of the objectives of uDebug is to help you debug your solutions by suggesting input test cases of a problem for which the system will show you the output of a solution that’s been deemed “accepted”. Which certainly makes debugging a lot of fun. For us, it can also serve to strengthen the test cases for problems which may have weak test data. There have been incidents in the past where users have reported weak test cases for our problems but there has been no mechanism to validate and get them added.
We instantly discussed a possible collaboration between CodeChef and uDebug by providing users an interface (https://www.udebug.com/) to challenge the test cases for CodeChef’s problems. It meant that now you will have the power to test any problem of CodeChef against your test cases and if the community agrees with you, you can get them added on CodeChef.
It gives us immense pleasure to announce that you can now try your test cases for CodeChef problems on uDebug.
What it means for you as a user is:
We have added problems from our practice section (excluding the Beginner and Peer section) to uDebug for you to try your test cases on. Feel free to go there and experiment with your test data and debug solutions to those problems that you have not been able to solve.
If your test cases pass and find enough love from the community, they will be added to the problems.
How do I report a weak test case?
If you discover that test cases for a problem on CodeChef is weak, add your suggested (stronger) test cases on uDebug and flag the problem.
If your suggested test cases gets enough up-votes from the community, just send them to us at: firstname.lastname@example.org
We will add those test cases to the problem.
And as always, there will be a reward waiting for you. What it will be, you will get to know when you report it.
We hope you enjoy playing around on uDebug and we look forward to a long and fruitful collaboration with them.
That will be all from us for now.
It was around three years ago, when our team mate, Suraj, had asked us to implement an automated system of sending goodies. We were struggling to deliver the users their winnings on time and quite a few of them would never reach their intended users. Not responded emails, faulty stale addresses, goodies getting lost in transit and tracking issues; left us hassled. We altered processes, included more checkpoints, reached out to our users, but nothing seemed to work.
Quite naturally, we liked the suggestion. The idea was to switch from a “push the goodie” system to “pull the goodie” one. Let the responsibility of getting a goodie be given to the users. We realised this would solve additional problems too, like the same user getting the same goodie multiple times, by giving her more options of accumulating points and winning something of a higher value.
This year, our growing struggle made us pick this up as a gift to ourselves and our users, as we turned seven. In the summer, with our intern, Raju Varshney, putting his hands up, we finally decided to put an all out effort to get this out. While he took up the coding, the rest of us scampered around to get an exciting new list of goodies prepared. And eventually the new system got ready to be served.
However, one thing at CodeChef is that we are a team full of pranksters! We love playing pranks on each other and we thought this to be a great time to include our users. It was long back that we did something similar and since then we have hardly done anything that grave! And this provided us with the perfect opportunity. It also served us as an experiment.
While we implemented the new system, we also decided to change the goodies to those of no monetary value to be considered as a token of appreciation for the effort put by the users. We wanted to see whether all our users want a goodie of monetary value or is it the winning that matters? We added three fun goodies on the site and kept our fingers crossed to see if one can spend her hard earned laddus against something that wasn’t initially promised – the duck, the cube and the ball.
And what we got was a pleasant surprise! Though we got a lot of criticism on the selection of our new goodies, we did find some of our users placing orders to actually get them! Kudos to them! Though we are removing those dummy goodies, we promise to give these users what they have ordered while reverting their laddus into their accounts. We had loads of fun and we hope that you would not mind this small prank of ours.
With this, we unveil the new goodie system. We have credited all your pending winnings as laddus into your account. Go ahead and check them out and have a look at the new goodies. And order whatever you like. We believe you will like some of them. In case you have any doubts or concerns regarding your laddus, do send us an email to email@example.com. Do not forget to read our terms and conditions to get more insight into the process and to not be disappointed later. We promise it is a good read.
SPOJ will be migrating CodeChef Judge to new servers today at 21:30(IST). This will be a quick migration and we will require a submission downtime of 15 mins. We will stop submissions after 21:30 for 15 minutes.
SPOJ will also be moving away from their current server and ISP, to a new server room and cloud. This will not affect the workings of the site in anyway.
Here’s everything you need to know about the entire migration.
You will not be able to make submissions into the ongoing August Challenge 2016 for 15 minutes starting 21:30 IST on 9th August 2016 to 21:45 IST on 9th August 2016.
The new judge servers are around 30-32% faster than the previous ones, hence, there will be some inconsistency in the execution time for the submissions made after the migration. However, you do not have to worry about the inconsistency as we will be re-judging all the submissions that ran on the old server at the end of August Challenge 2016.
That will be all for us. Should you have any questions or concerns, feel free to get in touch with us.
That he is talented and an emerging name to watch out for in the programming fraternity is something that we have already heard of Rajat De. And when he proved all that true, when he emerged atop the Indian rank table in our June Cook-Off 2016. We have seen some really celebrated names grace that place in the past, but with only 20 Cook-Offs under his belt, we think Rajat’s rise to the top is certainly worth celebrating. So, a big shout out to the wonder kid from Delhi Public School, Dwarka. We hope to see many such wonderful performances in the future.
Now, let’s take you to the other aspects of the contest. With Hasan Jaddouh as the problem setter, accompanied by Misha Chorniy and Pushkar Mishra as the tester and editorialist respectively, we had a perfect balance of seasoned and upcoming stars of our problem setting bench. And so were the participants, some new, some established, and some just starting their journey in the competitive programming world.
With over 7.5K submissions from 1689 participants in the two and half hour duration of the competition, we saw some great programming action among all the participants. And to find out who emerged atop, let’s take a tour de rank table.
We start with the ROW top 10:
Now, the Indian top 5:
The final stats for COOK71 were:
And now, the editorials:
We hope you had fun in the contest and munching the editorials. With that we move towards the final contest from June, the June LunchTime 2016. We will soon be publishing its story.
Till then, keep coding.
See you at the contests.