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How do I check if a C++ std::string starts with a certain string, and convert a substring to an int?

....rfind("titi") returns 2 so when compared against == 0 would return false) and it would be inefficient (looking through the whole string instead of just the start). But it does not do that because it passes the pos parameter as 0, which limits the search to only match at that position or earlier. Fo...
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How to sort my paws?

...nt experiment runs stored as ascii arrays. Rather than try to copy-paste stand-alone code examples into this question, here's a bitbucket mercurial repository with full, stand-alone code. You can clone it with hg clone https://joferkington@bitbucket.org/joferkington/paw-analysis Overview There...
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How do I calculate square root in Python?

...ve to write: sqrt = x**(1/2.0), otherwise an integer division is performed and the expression 1/2 returns 0. This behavior is "normal" in Python 2.x, whereas in Python 3.x 1/2 evaluates to 0.5. If you want your Python 2.x code to behave like 3.x w.r.t. division write from __future__ import division...
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How to check if a map contains a key in Go?

...ng here } Explanation: if statements in Go can include both a condition and an initialization statement. The example above uses both: initializes two variables - val will receive either the value of "foo" from the map or a "zero value" (in this case the empty string) and ok will receive a bool ...
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How do I use Assert to verify that an exception has been thrown?

...message is treated as a string that needs to matcvh the exception message (and IU think that makes more sense) – Ruben Bartelink Jun 25 '09 at 10:48 29 ...
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Visual Studio “Could not copy” … during build

...d success by doing the following: Closing Visual Studio Deleting the bin and obj folders, and Reopening Visual Studio. This "bug" has existed since Visual Studio 2003. Finally, I have also found that I can often overcome this problem by simply renaming the executable file and then deleting it. ...
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Maximum size of an Array in Javascript

Context: I'm building a little site that reads an rss feed, and updates/checks the feed in the background. I have one array to store data to display, and another which stores ID's of records that have been shown. ...
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Java: How to convert List to Map

...gue about what would be the optimal way to convert List to Map in Java and if there any specific benefits of doing so. ...
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How do I update an entity using spring-data-jpa?

... Identity of entities is defined by their primary keys. Since firstname and lastname are not parts of the primary key, you cannot tell JPA to treat Users with the same firstnames and lastnames as equal if they have different userIds. So, if you want to update a User identified by its firstname a...
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Objective-C ARC: strong vs retain and weak vs assign

...ew memory management attributes for properties introduced by ARC, strong and weak . 8 Answers ...