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What is the difference between “int” and “uint” / “long” and “ulong”?
...128 to 127. The 9th bit represents 256. So with 8 bits you can represent all values up to 255 (9th val - 1). The range from -128 to 127 has a length of exactly 255. So there is no bit that holds the sign. All values up to 127 are positive. Values above get displayed negative. 255 would be -1. 254 wo...
Hidden Features of MySQL
...
Since you put up a bounty, I'll share my hard won secrets...
In general, all the SQLs I tuned today required using sub-queries. Having come from Oracle database world, things I took for granted weren’t working the same with MySQL. And my reading on MySQL tuning makes me conclude that MySQL is be...
C++ cout hex values?
...
This seems to change all future output from cout to hex; so if you only want 'a' to be printed in hex you may want something like cout << hex << a << dec; to change it back.
– ShreevatsaR
M...
How do you manage databases in development, test, and production?
...of good options. I wouldn't use the "restore a backup" strategy.
Script all your schema changes, and have your CI server run those scripts on the database. Have a version table to keep track of the current database version, and only execute the scripts if they are for a newer version.
Use a migr...
What is a clearfix?
...of laying out elements.)
A clearfix is a way for an element to automatically clear its child elements, so that you don't need to add additional markup. It's generally used in float layouts where elements are floated to be stacked horizontally.
The clearfix is a way to combat the zero-height cont...
Unignore subdirectories of ignored directories in Git
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I have a global gitignore file where I ignored all *.zip file. Yet for a particular project, I want to include zip files. I added this line to that project's .gitignore and it works great!: !*.zip
– Jinghao Shi
Mar 21 '15 at 3:44
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Programmer Puzzle: Encoding a chess board state throughout a game
..., 2 bishops, 1 queen and 1 king as illustrated here:
Positions are generally recorded as a letter for the column followed by the number for the row so White’s queen is at d1. Moves are most often stored in algebraic notation, which is unambiguous and generally only specifies the minimal informa...
Convert Python program to C/C++ code? [closed]
...t * stuff). And it will never get quite as fast as plain C because it's usually interfacing with Python (100% or more? only for plain numerical code that doesn't interface with Python at all for the most time!). But other than that, yes, it can get you a pretty devent speedup.
–...
C# Sortable collection which allows duplicate keys
... Use this Comparer e.g. with SortedLists or SortedDictionaries, that don't allow duplicate keys
/// </summary>
/// <typeparam name="TKey"></typeparam>
public class DuplicateKeyComparer<TKey>
:
IComparer<TKey> where TKey : IComparable
{
#...
How does the main() method work in C?
...d nothing bad happens with their given compiler.
This is the case if the calling conventions are such that:
The calling function cleans up the arguments.
The leftmost arguments are closer to the top of the stack, or to the base of the stack frame, so that spurious arguments do not invalidate the ...