I'm leading a small group of developer at my university and I'd like to work through a couple of ICPC problem sets from previous years.
Searching on Google yields no useful results, just page upon page of broken links and private .edu domains.
Does anyone know where to find these problem sets from previous years?
Found the motherload here:
http://livearchive.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8
You might also like the following problems:
Google has posted some interesting problems. People also post their solutions, so you can see how others implemented a solution.
http://code.google.com/codejam/contests.html
Reddit is also another good source to get interesting problems.
http://www.reddit.com/r/programmingchallenges/
Related
I have added 'importfromweb' addon to scratch data from StockX. Unfortunately I faced with some issues and I don't really know how to solve this issue. If you look at the picture, you may see two links from StockX website with sneakers. You may also see Xpath copied from those two links insdicating to the price of the shoe above. Unfortunately the first shows an Error and I dont know why.
The arguments of the function are placed correcty
Links: https://stockx.com/air-jordan-36-flipped-infrared-23
https://stockx.com/air-jordan-36-low-black-multi-color
I have tried to search the reasons from the internet but I did not find anything about how to solve this problem
This is the first time I am trying to contribute to Mozilla. I went through several articles and documentation/resources to get a hang of what could be the best first steps to get started. I started off from this page http://whatcanidoformozilla.org1 and chose to start off with Java.
On initial tinkering I was taken to https://wiki.mozilla.org/Mobile/Get_Involved and eventually https://wiki.mozilla.org/Mobile/Fennec/Android/Suggested_workflow resource suggested that the best way to get started with it would be to pick up some simple bug and propose a patch for it.
So then I went to http://www.joshmatthews.net/bugsahoy/?java=1&simple=1 and this specific bug drew my attention. The description of the bug mentioned this :
There are some methods that we share (or can share) across our DB
implementations, like appending PARAM_SHOW_DELETED, PARAM_LIMIT, or
PARAM_PROFILE.
These are currently spread across LocalBrowserDB, TabsAccessor,
URLMetadata, and so on. It'd be nice to clean these up.
Question 1. Now how do I get some more context on what exactly is the bug and what is required to be done ?
As of now there seems to be 2 patches already submitted from what I understood (and please correct if my understanding is wrong here). So to get some context about the bug I went ahead and opened up the first patch submitted here.
It gave me some idea as to at least where exactly is the code itself that needs to be fixed. And I found it here
Question 2. Am I on the right track on how to figure out the code that needs to be fixed ?
Question 3. Even after reaching the DBUtils.java file I could not find any documentation about what the class basically does, or where does it fit into the whole picture. Could someone please help me with this, as to how do I figure out what a class is supposed to be doing etc. or at least some documentation around it?
You're on the right path. Basically, the What Can I Do For Mozilla website is a quick and easy way to let you discover projects you might be interested in, so it's the first gateway to the coding contributions.
That said, you did good in picking a bug to start off. However, as you saw the bug was already being worked on by somebody else (marked as Assigned). Your best bet is to find some new "good first bug" to work on. This might be a complicated task, as Bug's Ahoy shows only a few not owned good first bugs.
You should try to get in touch with the Fennec team, either via email or IRC (the latter for quicker responses).
Now, to answer your questions, in a more general way
Question 1. Now how do I get some more context on what exactly is the
bug and what is required to be done ?
Usually, this should be described in the first comment in the bug, on Bugzilla. If that's not the case, feel free to drop a message there and ask for more directions. You can also flag the reporter or the mentor of the bug using the needinfo functionality, as they are usually better shown.
As you can see, somebody asked for more info in comment 1 and some new directions were given.
In general, you won't find a patch with code on the bug itself, but you might find links to files and more precise directions on what to change and how. If not, again, feel free to ping the reporter and/or mentor.
Question 2. Am I on the right track on how to figure out the code that
needs to be fixed ?
You're on the right path. In general, if there are no links to files or DXR on the bug, but some code is mentioned, you can look it up using DXR, as you did.
Question 3. Even after reaching the DBUtils.java file I could not find
any documentation about what the class basically does, or where does
it fit into the whole picture. Could someone please help me with this,
as to how do I figure out what a class is supposed to be doing etc. or
at least some documentation around it?
What I usually do when navigating the Firefox code and need some more background on a not so well documented class, is browse the change log for that file, clicking on the Log button in the top-right panel on DXR (when displaying the file). It will show you a list of bugs that affected the file. You can even trace back the original file that implemented it, to get more context.
On the other hand, if you're only interested to the history of a single line of code within a file, then the blame tool is your friend. It tells you who last touched the line, the changeset and the related bug number. That is also accessible from where you can find the Log, here.
In the case of DBUtils.java, however, it looks like the class just holds some utility functions for database access.
To see how something is being used within the Firefox codebase, you can still use DXR. Here's a sample search for the DBUtils object.
Some days ago, some friends of mine told me to avoid using <iframe> for virtually anything, which of course includes Google Maps. That made me do some research and, among other things, find this thread in Quora (http://www.quora.com/Google-Maps/What-are-best-practices-and-recommendations-to-implement-Google-maps-within-an-iframe-on-a-webpage), which I think isn't conclusive, at least in my case. I've made a simple site which includes displaying a Google Map. I used an <iframe> because it is very simple and, as pointed out before, it is the option that Google offers within every map, so I guessed it was the optimal one.
My question is: using an <iframe> is always a bad solution, or in a simple case like mine (only displaying a location map), is it recommended?
Thank you all, please let me hear your thoughts on this,
João
Using an iframe is like having another page loaded in your browser. Which takes resources. I think this is what the suggestion to avoid it based on. But naturally, the solution is to avoid those who suggest that you should avoid something always. Just use it when it makes sense and know where to stop.
Some time ago I had accidentally found website which was apparently product of Microsoft research on fact extraction from the web, more specifically from the Wikipedia. Right now I would like to have better look into how it works, but the problem is i can't find it, maybe somebody knows what I am talking about and could give me directions or link to it?
Thank you!
There is a hint of it here:
http://research.microsoft.com/en-us/collaboration/global/scholar2005.aspx#Kaisser
Looks like MSR where sponsoring a Phd student who was working on it a few years ago. There is a link to his website, might be worth giving him a shout.
I'm looking for coding exercises that have solutions. I've checked out topcoder and codekata but neither seem to have user posted solutions (maybe I just can't find them?).
Basically I can (try) to figure out how I would solve a problem but what I want is to learn and expand my knowledge by see how other (better) coders would solve the same thing.
ProjectEuler has some good fairly good problems that lend themselves easily to a coded solution. There is no site supported help system, but simple google searches with the number of the problem you are working on normally has good results.
Once you solve the problem, you then have access to the site solution and a forum posting that shows other users' solutions so you can learn from them, (If you solve it first).
In TopCoder you can find the solutions in Competitions > Algorithms > Statistics > Match Archive, there you select a match and statistics will be displayed. After that by clicking "[*]" at the left side of the handle name, you will be lead to the solutions submitted by that coder.