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Can hash tables really be O(1)?
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You have two variables here, m and n, where m is the length of the input and n is the number of items in the hash.
The O(1) lookup performance claim makes at least two assumptions:
Your objects can be equality compared in O(1) time.
There will be few ha...
Count(*) vs Count(1) - SQL Server
Just wondering if any of you people use Count(1) over Count(*) and if there is a noticeable difference in performance or if this is just a legacy habit that has been brought forward from days gone past?
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SourceKitService Terminated
...e with Xcode where the error "Source Kit Service Terminated" is popping up and all syntax highlighting and code completion is gone in Swift. How can I fix this?
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NoSQL - MongoDB vs CouchDB [closed]
...noob when it comes to the NoSQL movement. I have heard lots about MongoDB and CouchDB. I know there are differences between the two. Which do you recommend learning as a first step into the NoSQL world?
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Using HTML5/JavaScript to generate and save a file
I've been fiddling with WebGL lately, and have gotten a Collada reader working. Problem is it's pretty slow (Collada is a very verbose format), so I'm going to start converting files to a easier to use format (probably JSON). I already have the code to parse the file in JavaScript, so I may as well ...
How to find all positions of the maximum value in a list?
... 0 for this is 2n, the list is iterated through 2x, once to determine max, and another time to find the positions of the max. A for loop that tracks the current max and its position might be more efficient for really long lists.
– radtek
Jan 8 '15 at 18:42
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Curious null-coalescing operator custom implicit conversion behaviour
...hen there is a lifted conversion involving two nullable types on the left-hand side of the coalescing operator.
I have not yet identified where precisely things go wrong, but at some point during the "nullable lowering" phase of compilation -- after initial analysis but before code generation -- we...
Link and execute external JavaScript file hosted on GitHub
... for this, now, by using jsdelivr.net.
Steps:
Find your link on GitHub, and click to the "Raw" version.
Copy the URL.
Change raw.githubusercontent.com to cdn.jsdelivr.net
Insert /gh/ before your username.
Remove the branch name.
(Optional) Insert the version you want to link to, as @version (if y...
Why is Swift compile time so slow?
... it compiles, so Xcode 6 GM now shows which Swift files are being compiled and the status of compilation in real time as you can see in this screenshot:
So this comes very handy to know which of your files is taking so long. In my case it was this piece of code:
var dic = super.json().mutableCop...
How to integrate nodeJS + Socket.IO and PHP?
...ntly been looking around, to find a good way to communicate between nodeJS and PHP. Here is the idea : nodeJS is still quite new, and it can be kind of tricky to develop a full application only with it. Moreover, you may need it only for one module of your project, like realtime notifications, chat,...