Ask HN: How can someone solve a code jam competition problem in 1.4 minutes?

There is a set list of topics that come up every year in these programming competitions, including:

* dynamic programming

* tries

* depth/breadth first traversal of a graph

* combinatorics

* graph colouring

* prime generation techniques

These topics are almost guaranteed to crop up every year, and the people who do well in these programming competitions learn all these techniques off by heart. They have their own library and macros which do all this stuff, and when they read the question they instantly see which technique they need to use and boom they're done. You have to remember that these people have been practising this stuff from a very early age, and that in many cases, spending hours and hours becoming good at this is their only way out of a crappy life (Eastern Europeans). However, being good at competitive programming has very little correlation with being a good software engineer (I think there is some analysis done by the likes of Google or Microsoft which proves this, I will try to find the link later).

However, University of Warsaw is one of the best unis in these kind of competitions and also the biggest source of graduate employees for Google, etc. Therefore, even though maybe doesn't prove you are a perfect programmer, it proves you are smart and capable of learning.

Yes, but you can be an excellent software engineer without being good at competitive programming.

I think you are talking about xiaowuc1, who is on top of scoreboard and having solved first problem's small data input in 1.4 mins.

FYI, he gave a Quora answer about his view on Competitive Programming http://qr.ae/dx4m6

"Especially in the United States, there's little glory to be had in doing programming contests. I've invested thousands of hours into them, solving problem after problem, writing line of code after line of code, for what? My peers, meanwhile, are off doing amazing things: some are doing ground-breaking research with professors, others are finding new passions that they only could have discovered at Stanford... the list goes on. I'll be retiring from competitive programming after World Finals this year, in part because I want to live a more normal life."

That's in 2013, and he is still participating in this year's contest, so I guess he is still in love with it :p

Anyway, I did my first code jam last year and also got my ego shattered when looking at the scoreboard. I passed the online qualification round though, but decided to stop since I think it's nonsense trying to complete with thousands of competitive programmers to get to top 1000 when I never practiced as much as them. I used to be like them when I did math contests in high school, so I know what it feels. It's not about your IQ or anything like that, it's just about practice, practice, practice.

It's up to you to decide whether competitive programming is good for your career. For me I'm still doing it occasionally for fun (not really competitive since I just pick problems in areas that I find interesting and do it alone), but since I'm already spend 8 hours a day at work and have a bunch of unfinished side projects in hand and a long list of other things I want to learn, I don't think it's worth spending thousands hours of my time to compete in such contests.

You can also refer to this https://news.ycombinator.com/item?id=9337863 . I think the situation is similar, as doing competitive programming means putting yourself in relative comparison with others. It's just a double edged sword =)

> Just reading the description of the question, writing the code and compiling will take me more than that.

I am pretty sure he skipped compiling! I am being serious here.

Honestly, I am not sure why you are surprised. Competitive programming is different from regular programming, and like every other field it require years of training and experience to become good.

After a while you just learn to recognize patterns and common topics.

I think your comparison to chess is a good one. Both chess and competitive programming require years of deliberate practice to become good.

Source: done both. Though I was only somewhat good at chess, I was fairly successful at programming contests a few years ago(not this guy's level good though).

> Is that person simply a genius? My ego is shattered beyond recognition. (Instead of being happy that I solved my first competition problem...)

Don't feel bad about yourself! Imagine a Java programmer writing their first haskell program and being surprised at how quickly haskell programmers are able to write code in haskell. That's how your post looks to me.

Yes, its possible to solve the first problem in 1.4 minutes. Serious competitive programmers(like the guy you mentioned) has a template prepared to solve the problems so that they can parse the input easily and besides the logic for the first problem is very simple.

Practice. I play guitar and I can now impress my mom and some friends, after years of practicing hard. But I'll never play as well as Slash or Tom Morello or even as good as the kids that sit and jam in guitar shops. It doesn't bother me (ok the kids does a little because they are clearly showing off). My point is that it is a good thing that many people are much better than you because it means there is so much left to learn in the field you are studying.

Btw, is it this competition? https://code.google.com/codejam

To get that fast you need to write around 1 line of code per 3 seconds with zero bugs. It might seem impossible but if you train with it as a goal you will eventually reach it. It is true though that people use libraries and such, but no library would save any time on this problem and prebuilding the print "Case X:" wouldn't save much more than a few seconds.

I was going to give a try to your problem to solve it 1.3 minutes, but you don't pose the problem, so no way to know if it is possible or not.

You can view it here now that the contest is over:

http://code.google.com/codejam/contest/6224486/dashboard

It's against the rules to post it while the contest is ongoing. But you can still join and try to solve today.