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Relationship between hashCode and equals method in Java [duplicate]
...ts is calculated according to both .equals() and .hashCode(), for instance keys in a HashMap.
As its name implies, it relies on hash tables, and hash buckets are a function of the object's .hashCode().
If you have two objects which are .equals(), but have different hash codes, you lose!
The part ...
Possible to perform cross-database queries with PostgreSQL?
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Note: As the original asker implied, if you are setting up two databases on the same machine you probably want to make two schemas instead - in that case you don't need anything special to query across them.
postgres_fdw
Use postgres_fdw (foreign ...
How can I add new array elements at the beginning of an array in Javascript?
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Use unshift. It's like push, except it adds elements to the beginning of the array instead of the end.
unshift/push - add an element to the beginning/end of an array
shift/pop - remove and return the first/last element of an array
A simple ...
Is main() really start of a C++ program?
... of the C++ program.
Some of the environment setup is not controllable (like the initial code to set up std::cout; however, some of the environment is controllable like static global blocks (for initializing static global variables). Note that since you don't have full control prior to main, you d...
How to compare if two structs, slices or maps are equal?
I want to check if two structs, slices and maps are equal.
5 Answers
5
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Unnamed/anonymous namespaces vs. static functions
... feature of C++ is the ability to create unnamed (anonymous) namespaces, like so:
11 Answers
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How to use LINQ to select object with minimum or maximum property value
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Sheridan
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answered May 27 '09 at 5:53
Ana BettsAna Be...
Using relative URL in CSS file, what location is it relative to?
When defining something like a background image URL in a CSS file, when using a relative URL, where is it relative to? For example:
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Which terminal command to get just IP address and nothing else?
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You can write a script that only return the IP like:
/sbin/ifconfig eth0 | grep 'inet addr' | cut -d: -f2 | awk '{print $1}'
For MAC:
ifconfig | grep "inet " | grep -v 127.0.0.1 | cut -d\ -f2
Or for linux system
hostname -i | awk '{print $3}' # Ubuntu
hostname -i ...
Bitwise operation and usage
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Bitwise operators are operators that work on multi-bit values, but conceptually one bit at a time.
AND is 1 only if both of its inputs are 1, otherwise it's 0.
OR is 1 if one or both of its inputs are 1, otherwise it's 0.
XOR is 1 only if exactly one of its input...