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

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

#1

Post by eranation »

I am doing my first code jam, I spent an hour or so on the first problem, and submitted (after 1 wrong attempt), and was pretty proud of myself. Then I looked at the first ranked person (some Standford student with a track record of competition)

He / She did it in 1.4 minutes.

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

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

p.s. the problems this year seem way harder than the qualification rounds samples they have there. I never felt more stupid in my life. I recommend anyone who has a steady programming job, to stay away from these competitions, even if you are considered the smartest coder at work. You will feel stupid and incompetent, (and humbled to the ground).

I wish I could see a video of one of them as they code.

Could it be that questions in competitions simply repeat themselves and they just pulled some similar code and just modified it?

what are the "secrets" of programming competitions? Is it like chess? if you practice enough past competitions you are pretty much ready to anything they'll throw at you?

Or are these people really, really smart? (Or I'm really really stupid? :))

Ego shattered to the floor, considering switching careers (and I'm considered a pretty good developer...)

Very humbling experience, perhaps too humbling.

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

#2

Post by tuscarok »

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).

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

#4

Post by codenut »

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.

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

#5

Post by eatitraw »

> 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.

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

#6

Post by malpiatko »

tuscarok wrote: post #2

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 lib…

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.

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

#7

Post by eranation »

aquelarre wrote: post #3

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.

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

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

#8

Post by tuscarok »

malpiatko wrote: post #6
tuscarok wrote: post #2

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 lib…

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.

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

#9

Post by Klockan »

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.

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

#10

Post by bjourne »

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

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