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Pointers in C: when to use the ampersand and the asterisk?
I'm just starting out with pointers, and I'm slightly confused. I know & means the address of a variable and that * can be used in front of a pointer variable to get the value of the object that is pointed to by the pointer. But things work differently when you're working with arrays, string...
Is 1.0 a valid output from std::generate_canonical?
I always thought random numbers would lie between zero and one, without 1 , i.e. they are numbers from the half-open interval [0,1). The documention on cppreference.com of std::generate_canonical confirms this.
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C# Object Pooling Pattern implementation
... the base class library (BCL). You can read the original GitHub issue here and view the code for System.Buffers. Currently the ArrayPool is the only type available and is used to pool arrays. There is a nice blog post here.
namespace System.Buffers
{
public abstract class ArrayPool<T>
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Why check both isset() and !empty()
Is there a difference between isset and !empty . If I do this double boolean check, is it correct this way or redundant? and is there a shorter way to do the same thing?
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Does MS SQL Server's “between” include the range boundaries?
...t_expression is greater than or
equal to the value of begin_expression
and less than or equal to the value of
end_expression.
DateTime Caveat
NB: With DateTimes you have to be careful; if only a date is given the value is taken as of midnight on that day; to avoid missing times within your ...
Maximum number of records in a MySQL database table
...utoincrement field. What would happen if I add milions of records? How to handle this kind of situations?
Thx!
8 Answers
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How do I compare two strings in Perl?
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See perldoc perlop. Use lt, gt, eq, ne, and cmp as appropriate for string comparisons:
Binary eq returns true if the left argument is stringwise equal to the right argument.
Binary ne returns true if the left argument is stringwise not equal to the right argument....
Java EE 6 @javax.annotation.ManagedBean vs. @javax.inject.Named vs. @javax.faces.ManagedBean
...s work kind of independent, they boot in application server initialization and scan classes of all artifacts including jar, ejb-jar, war and ear files in deployment time and gather and store some metadata about them, then when you need an object of a class at runtime they will give you instances of ...
How do I detect unsigned integer multiply overflow?
...ting a program in C++ to find all solutions of a b = c , where a , b and c together use all the digits 0-9 exactly once. The program looped over values of a and b , and it ran a digit-counting routine each time on a , b and ab to check if the digits condition was satisfied.
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Java Hashmap: How to get key from value?
If I have the value "foo" , and a HashMap<String> ftw for which ftw.containsValue("foo") returns true , how can I get the corresponding key? Do I have to loop through the hashmap? What is the best way to do that?
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