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Is there any advantage of using map over unordered_map in case of trivial keys?

...lookup ( amortized O(1) vs. O(log n) ). Most times I use a map, I use either int or std::string as the key type; hence, I've got no problems with the definition of the hash function. The more I thought about it, the more I came to realize that I can't find any reason of using a std::map ov...
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How do I check if a variable exists?

...' intstead of myVar. If the variable name is not known when the code is written, it will be stored in a string variable at runtime, and the check I posted will also work. – Ayman Hourieh May 9 '09 at 13:46 ...
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Why is “import *” bad?

It is recommended to not to use import * in Python. 12 Answers 12 ...
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No Multiline Lambda in Python: Why not?

I've heard it said that multiline lambdas can't be added in Python because they would clash syntactically with the other syntax constructs in Python. I was thinking about this on the bus today and realized I couldn't think of a single Python construct that multiline lambdas clash with. Given that ...
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How to get CRON to call in the correct PATHs

...rrect PATHs. When I run a Python script from shell the script runs fine as it uses the PATHs set in bashrc but when I use cron all the PATHs are not used from bashrc. Is there a file I can enter the PATHs into for cron like bashrc or a way to call the PATHs from bashrc? ...
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C++ STL Vectors: Get iterator from index?

... stl vector by index[], but now I need to copy just a chunk of the vector. It looks like vector.insert(pos, first, last) is the function I want... except I only have first and last as ints. Is there any nice way I can get an iterator to these values? ...
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What is the best way to ensure only one instance of a Bash script is running? [duplicate]

...st way to ensure only one instance of a given script is running - assuming it's Bash on Linux? 14 Answers ...
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Is int[] a reference type or a value type?

...n array to a function to check something. Should I just pass the array, as it will just pass the reference of it, or should I pass it as ref? ...
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Isn't it silly that a tiny favicon requires yet another HTTP request? How can I put the favicon into

... that these browsers still can't: Safari iOS Safari Firefox for Android With the above in mind, we can now use SVG Favicons with a reasonable degree of confidence. 2) Present the SVG as a Data URI The main objective here is to avoid HTTP Requests. As other solutions on this page have mentioned, a...
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How to output numbers with leading zeros in JavaScript [duplicate]

I can round to x amount of decimal places with math.round but is there a way to round left of the decimal? for example 5 becomes 05 if I specify 2 places ...