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How to remove item from list in C#?
...== 2);
resultList.Remove(itemToRemove);
When you are not sure the item really exists you can use SingleOrDefault. SingleOrDefault will return null if there is no item (Single will throw an exception when it can't find the item). Both will throw when there is a duplicate value (two items with the s...
postgresql list and order tables by size
How can I list all the tables of a PostgreSQL database and order them by size ?
7 Answers
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Disable ONLY_FULL_GROUP_BY
I accidentally enabled ONLY_FULL_GROUP_BY mode like this:
26 Answers
26
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What is tail recursion?
...return x;
} else {
return x + recsum(x - 1);
}
}
If you called recsum(5), this is what the JavaScript interpreter would evaluate:
recsum(5)
5 + recsum(4)
5 + (4 + recsum(3))
5 + (4 + (3 + recsum(2)))
5 + (4 + (3 + (2 + recsum(1))))
5 + (4 + (3 + (2 + 1)))
15
Note how every recur...
Determining 32 vs 64 bit in C++
...esentation. I prefer ENVIRONMENT64 / ENVIRONMENT32. Then I find out what all of the major compilers use for determining if it's a 64 bit environment or not and use that to set my variables.
// Check windows
#if _WIN32 || _WIN64
#if _WIN64
#define ENVIRONMENT64
#else
#define ENVIRONMENT32
#endif...
Handling warning for possible multiple enumeration of IEnumerable
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The problem with taking IEnumerable as a parameter is that it tells callers "I wish to enumerate this". It doesn't tell them how many times you wish to enumerate.
I can change the objects parameter to be List and then avoid the possible multiple enumeration but then I don't get the highes...
Determine if variable is defined in Python [duplicate]
...ime? This is not always obvious because (1) the variable could be conditionally set, and (2) the variable could be conditionally deleted. I'm looking for something like defined() in Perl or isset() in PHP or defined? in Ruby.
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How to select lines between two marker patterns which may occur multiple times with awk/sed
... @KasunSiyambalapitiya: Mostly it means I like to use it. Formally, it specifies that the next argument is (part of) the script that sed should execute. If you want or need to use several arguments to include the entire script, then you must use -e before each such argument; otherwise,...
Time complexity of Sieve of Eratosthenes algorithm
...oose upper-bound is n(1+1/2+1/3+1/4+1/5+1/6+…1/n) (sum of reciprocals of all numbers up to n), which is O(n log n): see Harmonic number. A more proper upper-bound is n(1/2 + 1/3 + 1/5 + 1/7 + …), that is sum of reciprocals of primes up to n, which is O(n log log n). (See here or here.)
The "find...
When would I use XML instead of SQL? [closed]
... would be more useful than the approach I've always used, which is storing all of my data in a (My)SQL database and then using PHP/Python/etc. to work with it on the web as needed.
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