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Big-O for Eight Year Olds? [duplicate]
...ore about what this means to my code. I understand the concepts mathematically, I just have a hard time wrapping my head around what they mean conceptually. For example, if one were to perform an O(1) operation on a data structure, I understand that the number of operations it has to perform won't...
Create Generic method constraining T to an Enum
... You don't gain much by including the other interfaces because almost all of the built-in value types implement all of those interfaces. This is especially true for constraints on a generic extension method, which is extremely handy for operating on enums, except for the fact that those extensi...
What is the difference between Scala's case class and class?
...xclusively depend on their constructor arguments.
This functional concept allows us to
use a compact initialization syntax (Node(1, Leaf(2), None)))
decompose them using pattern matching
have equality comparisons implicitly defined
In combination with inheritance, case classes are used to mimi...
MySQL remove all whitespaces from the entire column
Is there a way to remove all whitespaces from a specific column for all values?
5 Answers
...
Copy all files with a certain extension from all subdirectories
Under unix, I want to copy all files with a certain extension (all excel files) from all subdirectories to another directory. I have the following command:
...
What do people find difficult about C pointers? [closed]
...duling, actual CPU operations, or assembly-level memory management isn't really required.
When I was teaching, I found the following holes in students' understanding to be the most common source of problems:
Heap vs Stack storage. It is simply stunning how many people do not understand this, even...
Java - get pixel array from image
... is to be able to address pixel (x, y) from the image using int[x][y] . All the methods I have found do not do this (most of them return int[] s).
...
Make XAMPP/Apache serve file outside of htdocs [closed]
...st
<Directory C:\Projects\transitCalculator\trunk>
Order allow,deny
Allow from all
</Directory>
</VirtualHost>
Open your hosts file (C:\Windows\System32\drivers\etc\hosts).
Add
127.0.0.1 transitcalculator.localhost #transitCalculator
to the end of the fi...
makefile execute another target
...
Actually you are right: it runs another instance of make.
A possible solution would be:
.PHONY : clearscr fresh clean all
all :
compile executable
clean :
rm -f *.o $(EXEC)
fresh : clean clearscr all
clearscr:
cle...
Is there any advantage of using map over unordered_map in case of trivial keys?
... unordered_map.
Something else to keep in mind is that unordered_map generally uses more memory. map just has a few house-keeping pointers, and memory for each object. Contrarily, unordered_map has a big array (these can get quite big in some implementations), and then additional memory for each ob...