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How to count the frequency of the elements in an unordered list?
I need to find the frequency of elements in an unordered list
33 Answers
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Why use getters and setters/accessors?
...nt to say plane.takeOff(alt). What inner data fields need to be changed in order to put the plane into the takingOff mode is none of my concerns. And what other objects (breaks) the method notifies I don't want to know either.
– sbi
Aug 24 '12 at 9:35
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“Variable” variables in Javascript?
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COALESCE Function in TSQL
...type, they get implicitly cast to an appropriate data-type using data-type order of precedence.)
It's like ISNULL() but for multiple parameters, rather than just two.
It's also ANSI-SQL, where-as ISNULL() isn't.
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Is there a performance difference between i++ and ++i in C++?
...forms deep copies. In such cases, there is no argument, ++i is perhaps an order of magnitude more efficient than i++. They key is to get in the habit of using pre-increment whenever post-increment semantics are not actually required by your algorithm, and you'll then be in the habit of writing cod...
Node Version Manager install - nvm command not found
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this worked for me but in order to automate it i had to create profile first. "touch ~/.profile", "open ~/.profile" , paste above, save+ close. works in new windows now
– Sonic Soul
Jun 4 '16 at 15:47
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Library? Static? Dynamic? Or Framework? Project inside another project
...A Framework embodies some abstract design, with more behavior built in. In order to use it you need to insert your behavior into various places in the framework either by subclassing or by plugging in your own classes. The framework's code then calls your code at these points. The main control of th...
How do I use the conditional operator (? :) in Ruby?
... Small edit puts (true ? "true" : "false") with parenthesis. Otherwise the order of operations is not clear. When I first read this I was confused as I read it as (puts true) ? "true" : "false" then expected puts to return the boolean which then became the string value.
– Fres...
sql ORDER BY multiple values in specific order?
...rds with a certain value and return the row.
I would like to know if I can order by multiple values.
9 Answers
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Regular expression for floating point numbers
... and '-.' are invalid
'.1e3' is valid, but '.e3' and 'e3' are invalid
In order to support both '1.' and '.1' we need an OR operator ('|') in order to make sure we exclude '.' from matching.
[+-]? +/- sing is optional since ? means 0 or 1 matches
( since we have 2 sub expressions we need to put t...