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What is more efficient? Using pow to square or just multiply it with itself?

...d::chrono::high_resolution_clock::time_point from; }; int main (int argc, char* argv[]) { double total; Timer timer; total = 0.0; timer.start(); for (double i = 0.0; i < 1.0; i += 1e-8) total += std::pow (i,2); std::cout << "std::pow(i,2): " << timer.elapsed() <...
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How do I drop a foreign key constraint only if it exists in sql server?

...target a foreign key constraint on a specific table, use this: IF EXISTS (SELECT * FROM sys.foreign_keys WHERE object_id = OBJECT_ID(N'dbo.FK_TableName_TableName2') AND parent_object_id = OBJECT_ID(N'dbo.TableName') ) ALTER TABLE [dbo.TableName] DROP CONSTRAINT [FK_TableName_TableName2]...
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What are the various “Build action” settings in Visual Studio project properties and what do they do

... as a default... I'm referring to the BuildAction property for each file selected in Solution Explorer. There are a number of options and it's difficult to know what each one of them will do. ...
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How to collapse all methods in Xcode?

...upport for folding blocks of code from the folding ribbon, from structured selection, or from the Menubar ► Editor ► Code Folding ► Fold menu item Look at this snapshot: Code folding was disabled in Xcode 9 beta 1, which is working now, in Xcode 9 Beta5 according to beta relea...
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Cannot generate iOS App archive in xcode

...using your archive to create an archive file rather than an ipa do this: Select the archive and click the Distribute button. Select the 'Save Built Products' option. Hit Next and Save. Browse the created directory in Finder. The 'libraries' subdirectory will identify the libraries that you nee...
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How to easily initialize a list of Tuples?

..." }, new Hold { Id = 2, Name = "You" } }; var anonymousProjections = holds.Select(x => new { SomeNewId = x.Id, SomeNewName = x.Name }); var namedTuples = holds.Select(x => (TupleId: x.Id, TupleName: x.Name)); Reuse the tuples later with grouping methods or use a method to construct the...
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What's the @ in front of a string in C#?

...also allows multi-line contents - which can be very handy for SQL: string select = @" SELECT Foo FROM Bar WHERE Name='Baz'"; The one bit of escaping which is necessary for verbatim string literals is to get a double quote (") which you do by doubling it: string verbatim = @"He said, ""Would you ...
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What is the lifetime of a static variable in a C++ function?

... emitter a("in if"); static emitter b("in foo"); } int main(int argc, char*[]) { foo(argc != 2); if (argc == 3) foo(false); } Output: C:>sample.exe Created in foo Destroyed in foo C:>sample.exe 1 Created in if Created in foo Destroyed in foo Destroyed in if C:>sample...
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How to fix “Referenced assembly does not have a strong name” error?

...at does not "have a strong name key", do Right click on the project file Select Properties Select "Signing tab" (on the left) Click the check box "Sign the assembly" Then <Browse> to the .snk file you found earlier That should do the trick. This solved a problem for me for one project usin...
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How do you automatically set text box to Uppercase?

...ly expanded version should resolve that <input oninput="let p=this.selectionStart;this.value=this.value.toUpperCase();this.setSelectionRange(p, p);" /> share | improve this answer ...