Candy Corns,
By popular demand you can now view all submissions for practice problems which you have successfully solved. You’ve solved a problem in Java, you can now see how someone else solved it in C. Hopefully you will use this power for good, and learn from other members as well as assist those who are having trouble.

How else can we improve the site? What can we do, to help you become better programmers?

Let us know,
Amit

Chocolate Chips,
We’ve been hard at work developing a new and improved CodeChef 2.0 site. Here’s a short list of features you can expect in the coming weeks: shoutbox/chat, campus dashboards, a help wiki, rankings page, individual statistics, levels, awards and more…

Take a look:

This is not a final mockup but hints at some of the new features we are rolling out. You’ll start seeing updates in the next few weeks. Enjoy!

Cheers,
Chef

Greetings everyone!

We are happy to introduce a rating system for Codechef based on the contests we have every month. In brief, the rating system will have the following features.

1. Every user will have a rating. The user with the highest rating will be ranked 1, the user with the next highest rating will be ranked 2 and so on.

2. The ratings for the users will depend only on how they perform in the contests and not how they perform in the practice section.

3. Every contest problem will get a particular value based on the number of users solving that problem. The maximum value for a problem tends to the value 5 and the minimum value for a problem tends to 1. So, every user is guaranteed at-least 1 point for solving a problem. The selection of the value 5 was to give sufficient room for the top performers to increase their rating. Selection of a smaller range of values would let those participants solving only easy problems and participating frequently overtake those not participating frequently but performing exceptionally well when they do. Suppose the total number of users who have solved a particular problem is PS and the total number of users who have participated in the contest is TS, then the point value for a particular problem is 5 - 4*PS/TS. So, if there are more users successfully solving a problem, it’s value will be less and vice versa.

4. Suppose a user has solved P problems and at the end of the contest, these problems have the values V1, V2, .. ,Vp, then the total rating score S of the user for that contest will be V1+V2+…+Vp.

5. The new rating of the user will be old_rating+S.

Also, every user’s profile page will now have a rating graph along with the current rating and rank. Your feedback in this regard is much appreciated

Regards,
Aniruddha.

Note : Because of some server-side issues we have disabled the chat feature as of now. It will be back as soon as we get things in place on the server.

Greetings Everyone !

In a bid to encourage interaction among users, we have introduced a shout-out box where people can chat or discuss anything that interests them. Currently, the shout-out box is visible at the bottom of the screen and the last two messages received are displayed. When you click on it, you get a bigger shout-out box where you can type messages, if logged in.

We hope that you will not misuse this functionality. You can get back to us with the feedback at admin@codechef.com or by leaving a comment on this post.

Happy Chatting !

Regards,
Aniruddha.

Greetings everyone !

We have just shifted our site to a CMS named Drupal. The major reasons for doing this is the amount of flexibility it offers in terms of introducing new features and modules. The new site was launched a few hours ago and I am sure most of you have figured out that something has changed We want your feedback on this. Also, if you face any issues, or find broken links, you can post them as a comment or get back to us at admin@codechef.com

Looking forward to your take on our new site. Happy coding.

Regards,
Aniruddha.

Greetings,

Over the past few weeks we have been thinking of implementing some kind of a rating system on Codechef. We would like your opinions on a few aspects of the rating system. Some of the areas on which we would like your help are :

Fixed points for problems vs. Variable points for problems.
As of now, all our problems have a value of 1 (other than the challenge problem where only the best submission gets a value of 1 and all others get a value relative to that). Should we have the same points for all problems (other than the challenge type) or should the points for each problem vary according to the number of submissions for that problem. Along with the contest problems, this could extend to practice problems as well. So, the points awarded for solving a problem X having N users who have submitted correct solutions could be 1/N or some variant of this. If a new correct solution for one of the problems were to be submitted, we would change the points awarded for that problem accordingly. So, if someone were to solve a lot of easy problems, he/she would get less points compared to someone who would solve a really tough problem having fewer correct submissions. Any suggestions on what parameters we could consider while determining the points awarded to a problem would be welcome.

Cummulative rating vs. Dynamic rating based on ranks in a contest.
Every user would have a rating which would depend on his / her performance in a contest. There are two methods that we feel could be used for this. The first would be that the rating of the user is simply the sum of the points of the problems he / she has solved in the contest. The other method would be to base his rating on his actual rank in the contest and his expected rank based on his performance in the previous contests. If a participant performs poorly compared to his expected ranking, he would experience a rating drop and if he performs better than his expected ranking, he would get an increase in rating. Again, if you have any suggestions on what parameters we can consider while calculating the ratings for a particular user, they would be helpful.

Looking forward to your replies

Cupcakes,
You’ve asked for it, we’ve done it. A big complaint people have had was the time limits were too strict for programming languages that didn’t start with a C. There are now variable time limits depending on the programming language you have used to submit your solution. The current time limits are as follows (as a multiplier to the time limit listed on the problem page):

• Java - 2X
• Python - 2X
• Ruby - 3X
• PHP - 3X
• Lisp - 3X
• All other languages - 1X

We will continue to tweak the exact multipliers  and will let you know if there are any other modifications.  Solutions will not be rejudged, you will be required to submit new solutions to see if your program now satisfies the time limit conditions.

Cheers,

The Chef

Hash Browns,

Our goals with CodeChef are to challenge and engage the developer community as well as provide a platform for competition and improvement.  We’ve heard from many people that when they get a wrong answer or time limit exceeded they aren’t sure how to debug their submissions.  We are working on a few ways to improve this:

• Additional tutorials describing various approaches to debugging and reducing execution time.
• An interactive mode which allows you to specify inputs which will run on our testing infrastructure and display the output (possibly only available in the practice arena).  This will allow you to debug any infrastructure or compiler differences and see how your code runs on the machine it is evaluated on.
• Additional information on submissions (possibly only available in the practice arena) - For each test case, the number of inputs, the result, execution time and time limit.   This will let you know if your approach is correct and you just need to optimize your solution to fit within the time limits, or if it’s back to the drawing board.

For our April Contest, we will also be experimenting with another major change.  After the contest is over we will make all code submissions for problems within that contest, publicly available.  Eventually we plan to allow comments on individual submissions as well.  We hope this will allow less experienced developers to learn from their peers and generally promote knowledge sharing.  We look forward to hearing your feedback on these initiatives.

Cheers,

The Chef

It’s been just over a month since we’ve launched and we’re really excited about the way things are going.  We now have over a thousand registered users and accept hundreds of code submissions a day.  The response has been great, but we’re not done.   As a way to continue to challenge, engage and give back to the developer community, we’re pumped to announced a few new initiatives.

CodeChef Campus Chapters - Are you a student interested in setting up a CodeChef Chapter on your campus?  Each month we’ll send you optimal solutions to specific contest problems, tips & tools to become better software developers and (of course) some awesome CodeChef merchandise (everyone looks cool in chef’s hat).

Blogger Community Program - Are you a blogger interested in spreading the word about CodeChef?  We got what you need: exclusive access to content, press passes and more.

User Group Outreach Program - Are you part of a user group which is enthusiastic about programming?  We’ll give you a place for your meetings, and a chance for your users to network and gain recognition.

First contest starts Sunday, keep practicing…

CodeCheffers,
By popular demand we have added a trivial sample question: Life, the Universe, and Everything.   Solutions in 25 programming languages can be found in our forums.

Additionally we’ve added a few new, easy practice problems:

Enormous Input Test
Sums in a Triangle
Turbo Sort
The Way to a Friends House Is Never Too Long

Finally we moved some of the more difficult of the easy problems to medium.  As always your feedback appreciated.