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Convert a positive number to negative in C#

...itive ones negative. This approach has a single flaw. It doesn't work for all integers. The range of Int32 type is from "-231" to "231 - 1." It means there's one more "negative" number. Consequently, Math.Abs(int.MinValue) throws an OverflowException. The correct way is to use conditional stateme...
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Using Laravel Homestead: 'no input file specified'

... Instead of reinstalling try vagrant up --provision or homestead up --provision share | improve this answer | fo...
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INNER JOIN vs LEFT JOIN performance in SQL Server

... slower; by definition, an outer join (LEFT JOIN or RIGHT JOIN) has to do all the work of an INNER JOIN plus the extra work of null-extending the results. It would also be expected to return more rows, further increasing the total execution time simply due to the larger size of the result set. (A...
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How to remove spaces from a string using JavaScript?

...s is the regex for "whitespace", and g is the "global" flag, meaning match ALL \s (whitespaces). A great explanation for + can be found here. As a side note, you could replace the content between the single quotes to anything you want, so you can replace whitespace with any other string. ...
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What is the purpose of the '@' symbol in CSS?

...ructs. The @ syntax itself, though, as I mentioned, is not new. These are all known in CSS as at-rules. They're special instructions for the browser, not directly related to styling of (X)HTML/XML elements in Web documents using rules and properties, although they do play important roles in control...
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Ruby off the rails

... the huge benefits of Ruby is the ability to create DSLs very easily. Ruby allows you to create "business rules" in a natural language way that is usually easy enough for a business analyst to use. Many Ruby apps outside of web development exist for this purpose. I highly recommend Googling "ruby ...
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What do two question marks together mean in C#?

...e following statement will assign the first non-null Answer# to Answer (if all Answers are null then the Answer is null): string Answer = Answer1 ?? Answer2 ?? Answer3 ?? Answer4; Also it's worth mentioning while the expansion above is conceptually equivalent, the result of each expression is o...
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How to show the last queries executed on MySQL?

Is there any query/way to show the last queries executed on ALL servers? 10 Answers ...
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Xcode 5: Code signing entitlement errors

...both rows, however, I saw the "Any iOS SDK" subrows for each configuration all set to None, although the Debug/Release rows did list the proper profile/signing identity. Archiving in this state still gave me the error, until I explicitly set all the "Any iOS SDK" rows to their proper values. ...
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How to simulate Android killing my process

...tivityA instead. This is what Android docs are saying about that: Normally, the system clears a task (removes all activities from the stack above the root activity) in certain situations when the user re-selects that task from the home screen. Typically, this is done if the user hasn't visited ...