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Rounding up to next power of 2
I want to write a function that returns the nearest next power of 2 number. For example if my input is 789, the output should be 1024. Is there any way of achieving this without using any loops but just using some bitwise operators?
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How to upgrade PostgreSQL from version 9.6 to version 10.1 without losing data?
I'm using the PostgreSQL database for my Ruby on Rails application (on Mac OS X 10.9).
15 Answers
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What is the syntax for a default constructor for a generic class?
Is it forbidden in C# to implement a default constructor for a generic class?
3 Answers
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PHP parse/syntax errors; and how to solve them
Everyone runs into syntax errors. Even experienced programmers make typos. For newcomers, it's just part of the learning process. However, it's often easy to interpret error messages such as:
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Random row from Linq to Sql
What is the best (and fastest) way to retrieve a random row using Linq to SQL when I have a condition, e.g. some field must be true?
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How do I get hour and minutes from NSDate?
In my application I need to get the hour and minute separately:
8 Answers
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Java List.add() UnsupportedOperationException
I try to add objects to a List<String> instance but it throws an UnsupportedOperationException .
Does anyone know why?
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Is there a performance difference between i++ and ++i in C?
Is there a performance difference between i++ and ++i if the resulting value is not used?
14 Answers
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How to validate phone numbers using regex
I'm trying to put together a comprehensive regex to validate phone numbers. Ideally it would handle international formats, but it must handle US formats, including the following:
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Query EC2 tags from within instance
Amazon recently added the wonderful feature of tagging EC2 instances with key-value pairs to make management of large numbers of VMs a bit easier.
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