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Why '&&' and not '&'?
Why is && preferable to & and || preferable to | ?
16 Answers
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Why does GCC generate 15-20% faster code if I optimize for size instead of speed?
I first noticed in 2009 that GCC (at least on my projects and on my machines) have the tendency to generate noticeably faster code if I optimize for size ( -Os ) instead of speed ( -O2 or -O3 ), and I have been wondering ever since why.
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What is Bit Masking?
I am fairly new to C programming, and I encountered bit masking. Can someone explain to me the general concept and function of bit masking? Examples are much appreciated.
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Ruby Bundle Symbol not found: _SSLv2_client_method (LoadError)
I was doing attempting to do some updates to openssl using homebrew and I somehow managed to break everything. I can't do anything now, this is what I get when I try to do bundle install:
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How to create the most compact mapping n → isprime(n) up to a limit N?
...test, you should probably run a probabilistic test since those are faster, and then follow it up with a deterministic test to make sure the number is prime.
You should know that the math behind the fastest algorithms is not for the faint of heart.
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Make xargs execute the command once for each line of input
How can I make xargs execute the command exactly once for each line of input given?
It's default behavior is to chunk the lines and execute the command once, passing multiple lines to each instance.
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Printf width specifier to maintain precision of floating-point value
...eventh = 1.0/7.0 results in the value below. Also shown are the preceding and following representable double floating point numbers.
OneSeventh before = 0.1428571428571428 214571170656199683435261249542236328125
OneSeventh = 0.1428571428571428 49212692681248881854116916656494140625
OneSeven...
How do iOS Push Notifications work?
...ered to receive those notifications. Each device establishes an accredited and encrypted IP connection with the service and receives notifications over this persistent connection. Providers connect with APNs through a persistent and secure channel while monitoring incoming data intended for their cl...
Similarity String Comparison in Java
I want to compare several strings to each other, and find the ones that are the most similar. I was wondering if there is any library, method or best practice that would return me which strings are more similar to other strings. For example:
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Simplest PHP example for retrieving user_timeline with Twitter API version 1.1
... It has taken me over one working week to be provided a set of API tokens, and this is for an open source project for you guys and girls with over 1.2 million installations on Packagist and 1.6k stars on Github, which theoretically should be higher priority.
If you are tasked with working with the t...