大约有 40,000 项符合查询结果（耗时：0.0273秒） [XML]
Recursion or Iteration?
...n if the recursive function is tail recursive (the last line is recursive call). Tail recursion should be recognized by the compiler and optimized to its iterative counterpart (while maintaining the concise, clear implementation you have in your code).
I would write the algorithm in the way that m...
Passing parameters to a Bash function
...n_name {
command...
}
or
function_name () {
command...
}
To call a function with arguments:
function_name "$arg1" "$arg2"
The function refers to passed arguments by their position (not by name), that is $1, $2, and so forth. $0 is the name of the script itself.
Example:
function_n...
How do getters and setters work?
I'm from the php world. Could you explain what getters and setters are and could give you some examples?
6 Answers
...
Using Default Arguments in a Function
...= "some other value";
}
code here!
}
This way, you can make a call like foo('blah', null, 'non-default y value'); and have it work as you want, where the second parameter $x still gets its default value.
With this method, passing a null value means you want the default value for one par...
How to think in data stores instead of databases?
...ntiguous ranges of keys. More sophisticated queries are made possible with indexes, which are basically just tables of their own, allowing you to implement more complex queries as scans on contiguous ranges.
Once you've absorbed that, you have the basic knowledge needed to understand the capabilitie...
Is there a performance difference between a for loop and a for-each loop?
...of the clutter
and the opportunity for error by
hiding the iterator or index variable
completely. The resulting idiom
applies equally to collections and
arrays:
// The preferred idiom for iterating over collections and arrays
for (Element e : elements) {
doSomething(e);
}
When y...
Duplicating a MySQL table, indices, and data
...
To copy with indexes and triggers do these 2 queries:
CREATE TABLE newtable LIKE oldtable;
INSERT INTO newtable SELECT * FROM oldtable;
To copy just structure and data use this one:
CREATE TABLE tbl_new AS SELECT * FROM tbl_old;
I'...
NOT IN vs NOT EXISTS
... explained here. It is all there to convert the previous single correlated index seek on Sales.SalesOrderDetail.ProductID = <correlated_product_id> to two seeks per outer row. The additional one is on WHERE Sales.SalesOrderDetail.ProductID IS NULL.
As this is under an anti semi join if that ...
Pythonic way to find maximum value and its index in a list?
...value in a list, I can just write max(List) , but what if I also need the index of the maximum value?
10 Answers
...
What are the differences between utf8_general_ci and utf8_unicode_ci? [duplicate]
...tf8_unicode_ci uses the standard Unicode Collation Algorithm, supports so called expansions and ligatures, for example:
German letter ß (U+00DF LETTER SHARP S) is sorted near "ss"
Letter Π(U+0152 LATIN CAPITAL LIGATURE OE) is sorted near "OE".
utf8_general_ci does not support expansions/liga...