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Performance optimization strategies of last resort [closed]

...erformance questions on this site already, but it occurs to me that almost all are very problem-specific and fairly narrow. And almost all repeat the advice to avoid premature optimization. ...
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How to remove all leading zeroes in a string

...oat however, it seems to work ok. Strange – JamesHalsall Feb 23 '11 at 23:37 manual says that "The size of an integer ...
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Do rails rake tasks provide access to ActiveRecord models?

... namespace :test do task :new_task => :environment do puts Parent.all.inspect end end Notice the => :environment dependency added to the task share | improve this answer | ...
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Difference between .on('click') vs .click()

....on over .click because the former can use less memory and work for dynamically added elements. Consider the following html: <html> <button id="add">Add new</button> <div id="container"> <button class="alert">alert!</button> </div> <...
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Finding all possible combinations of numbers to reach a given sum

How would you go about testing all possible combinations of additions from a given set N of numbers so they add up to a given final number? ...
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Finding all possible permutations of a given string in python

I have a string. I want to generate all permutations from that string, by changing the order of characters in it. For example, say: ...
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Invoke a callback at the end of a transition

...// d3 v5 d3.select("#myid").transition().style("opacity","0").on("end", myCallback); // old way d3.select("#myid").transition().style("opacity","0").each("end", myCallback); This demo uses the "end" event to chain many transitions in order. The donut example that ships with D3 also uses this to ...
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Remove directory from remote repository after adding them to .gitignore

...h to rewrite the history - there is a helpful guide to that here. Additionally, note the output from git rm -r --cached some-directory will be something like: rm 'some-directory/product/cache/1/small_image/130x130/small_image.jpg' rm 'some-directory/product/cache/1/small_image/135x/small_image.jpg...
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What is the difference between public, protected, package-private and private in Java?

...e MyClass and I'm doing AnotherClass extends MyClass I will have access to all protected and public methods and properties from within AnotherClass. If I do MyClass myClass = new MyClass(); in AnotherClass somewhere - let's say the constructor - I will only have access to the public methods if it is...
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Why have header files and .cpp files? [closed]

...dencies so that code that uses the header doesn't necessarily need to know all the details of the implementation and any other classes/headers needed only for that. This will reduce compilation times and also the amount of recompilation needed when something in the implementation changes. It's not ...