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Find the Smallest Integer Not in a List
...a single entry with a value greater than the number of entries that can be allocated into the array. If the question did not specify 'very long', the answer is elegant, even if it destroys the input. The time-space trade off is very apparent in this problem, and a O(N) solution may not be possible...
Append an object to a list in R in amortized constant time, O(1)?
... single operation occasionally takes much longer than normal (e.g. if a preallocated buffer is exhausted and occasionally requires resizing to a larger buffer size), as long as the long-term average performance is constant time, we'll still call it O(1).
For comparison, I will also describe "linear...
MySQL: Fastest way to count number of rows
...ach time you try to count all rows. (based on primary key's column)
Using PHP to count rows is not very smart, because you have to send data from mysql to php. Why do it when you can achieve the same on the mysql side?
If the COUNT(*) is slow, you should run EXPLAIN on the query, and check if inde...
How to validate phone numbers using regex
... phone number is 1' OR 1=1 -- PWNED. See xkcd.com/327 and owasp.org/index.php/Testing_for_SQL_Injection_(OWASP-DV-005)
– Aaron Newton
Sep 19 '13 at 8:31
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Get first n characters of a string
How can I get the first n characters of a string in PHP? What's the fastest way to trim a string to a specific number of characters, and append '...' if needed?
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Types in MySQL: BigInt(20) vs Int(20)
...111000 (length 39 characters)
If you have INT(20) for system this means allocate in memory minimum 20 bits. But if you'll insert value that bigger than 2^20, it will be stored successfully, only if it's less then INT(32) -> 2147483647 (or 2 * INT(32) -> 4294967295 for UNSIGNED)
Example:
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Sort an Array by keys based on another Array?
Is it possible in PHP to do something like this? How would you go about writing a function? Here is an example. The order is the most important thing.
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Convert JavaScript String to be all lower case?
...triNg".toLowerCase()
Here's the function that behaves exactly the same as PHP's one (for those who are porting PHP code into js)
function strToLower (str) {
return String(str).toLowerCase();
}
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Global variables in Javascript across multiple files
...copy/pasted" into your HTML page before the page is rendered. Or into your PHP page if you will. Please correct me if I'm wrong here. Thanx.
My example files follow:
EXTERNAL JS:
var global = 0;
function f1()
{
alert('fired: f1');
global = 1;
alert('global changed to 1');
}
function...
Why am I seeing an “origin is not allowed by Access-Control-Allow-Origin” error here? [duplicate]
...ot the case you cannot use jsonp and you MUST rely on a server side proxy (PHP, ASP, etc.). There are plenty of guides related to this topic, just google it!
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