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Is there a performance difference between i++ and ++i in C++?
...it, even if you are not right now.
Knuth.
Premature optimization is the root of all evil. As is premature pessimization.
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Why can't decimal numbers be represented exactly in binary?
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The root (mathematical) reason is that when you are dealing with integers, they are countably infinite.
Which means, even though there are an infinite amount of them, we could "count out" all of the items in the sequence, withou...
How do I create a nice-looking DMG for Mac OS X using command-line tools?
...get as dependent target. You can access files in the Xcode tree using ${SRCROOT} in the script (is always the source root of your product) and you can access build products by using ${BUILT_PRODUCTS_DIR} (is always the directory where Xcode creates the build results).
Result: Actually Xcode can pro...
How to show all privileges from a user in oracle?
...d ones
WITH ALL_ROLES_FOR_USER AS (
SELECT DISTINCT CONNECT_BY_ROOT GRANTEE AS GRANTED_USER, GRANTED_ROLE
FROM DBA_ROLE_PRIVS
CONNECT BY GRANTEE = PRIOR GRANTED_ROLE
)
SELECT
PRIVILEGE,
OBJ_OWNER,
OBJ_NAME,
USERNAME,
REPLACE...
How to change the session timeout in PHP?
...p_value session.save_path "folderA/sessionsA".
So create a folder to your root server, not into the public_html and not to be publicity accessed from outside. For my cpanel/server worked fine the folder permissions 0700. Give a try...
php code =
Why does C++ need a separate header file?
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To my (limited - I'm not a C developer normally) understanding, this is rooted in C. Remember that C does not know what classes or namespaces are, it's just one long program. Also, functions have to be declared before you use them.
For example, the following should give a compiler error:
void S...
When to use the different log levels
...ow only warnings and errors may give quick insight into early hints at the root cause of a subsequent error. Warnings should be used sparingly so that they don't become meaningless. For example, loss of network access should be a warning or even an error in a server application, but might be just ...
Avoiding if statement inside a for loop?
... In that case, keep in mind that premature optimization is the root of all evil. When programming, always focus on code readability and make sure others understand what you are trying to do. Only consider micro-optimizations and various hacks after profiling your program and identifying ...
Why should hash functions use a prime number modulus?
...s again a polynomial of the same degree N (or less). It has no more than N roots (this is here the nature of math shows itself, since this claim is only true for a polynomial over a field => prime number). So if N is much less than P, you are likely not to have a collision. After that, experiment...
How to get the Full file path from URI
...nd of unique id per storage
// don't know any API that can get the root path of that storage based on its id.
//
// so no "primary" type, but let the check here for other devices
if ("primary".equalsIgnoreCase(type)) {
fullPath = Environment.getExternalSto...