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What's the difference between isset() and array_key_exists()? [duplicate]
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array_key_exists will definitely tell you if a key exists in an array, whereas isset will only return true if the key/variable exists and is not null.
$a = array('key1' => 'フーバー', 'key2' => null);
isset($a['key1']); ...
When should I use the “strictfp” keyword in java?
I've looked up what this does, but does anyone actually have an example of when you would use the strictfp keyword in Java? Has anyone actually found a use for this?
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How to find the kth smallest element in the union of two sorted arrays?
This is a homework question. They say it takes O(logN + logM) where N and M are the arrays lengths.
17 Answers
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UnboundLocalError on local variable when reassigned after first use
... assign values to them from inside or outside the function. If a variable is assigned within a function, it is treated by default as a local variable. Therefore, when you uncomment the line you are trying to reference the local variable c before any value has been assigned to it.
If you want the ...
Is it possible to ping a server from Javascript?
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I have found someone that accomplishes this with a very clever usage of the native Image object.
From their source, this is the main function (it has dependences on other parts of the source but you get the idea).
function Pinger_ping(ip, callback) {
i...
how to implement a pop up dialog box in iOS
After a calculation, I want to display a pop up or alert box conveying a message to the user. Does anyone know where I can find more information about this?
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Why there is no ConcurrentHashSet against ConcurrentHashMap
HashSet is based on HashMap.
9 Answers
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Is Unit Testing worth the effort? [closed]
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Every day in our office there is an exchange which goes something like this:
"Man, I just love unit tests, I've just been able to make a bunch of changes to the way something works, and then was able to confirm I hadn't broken anything by running the ...
How to concatenate a std::string and an int?
I thought this would be really simple but it's presenting some difficulties. If I have
23 Answers
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What's the difference between ASCII and Unicode?
...h not all numbers are currently assigned, and some are reserved).
Unicode is a superset of ASCII, and the numbers 0–127 have the same meaning in ASCII as they have in Unicode. For example, the number 65 means "Latin capital 'A'".
Because Unicode characters don't generally fit into one 8-bit byte...