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Will strlen be calculated multiple times if used in a loop condition?
...i] != '\0'; i++)
{
//Something;
}
In the above code str[i] only verifies one particular character in the string at location i each time the loop starts a cycle, thus it will take less memory and is more efficient.
See this Link for more information.
In the code below every time the loop runs str...
How to prevent form from being submitted?
... can not explain it more than Chris Baker did.
Both are correct, but none of them are "best" per se, and there may be
a reason the developer chose to use both approaches.
share
|
improve thi...
Best way to clear a PHP array's values
Which is more efficient for clearing all values in an array? The first one would require me to use that function each time in the loop of the second example.
...
Django - “no module named django.core.management”
...(at least for that version of python).
It is possible you have more than one version of python installed and django is inside of another version. You can find out all the versions of python if you type python and then press TAB. Here are all the different python's I have.
$python
python ...
How to copy a java.util.List into another java.util.List
...st<SomeBean> that is populated from a Web Service. I want to copy/clone the contents of that list into an empty list of the same type. A Google search for copying a list suggested me to use Collections.copy() method. In all the examples I saw, the destination list was supposed to contain th...
Case insensitive 'in'
...st. (name.upper() for name in USERNAMES) would create only a generator and one needed string at a time - massive memory savings if you're doing this operation a lot. (even more savings, if you simply create a list of lowercase usernames that you reuse for checking every time)
–...
AngularJS - Trigger when radio button is selected
I searched and tried many ng-xxxx kind of options but couldn't find the one..
I just want to call some function in the controller when radio button is selected.
...
How do you make a LinearLayout scrollable?
...r view" which means to say it's pointless to have a linearlayout with only one item.
– Niels
Nov 19 '15 at 6:48
2
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SQL/mysql - Select distinct/UNIQUE but return all columns?
...ach time.
On some platforms (e.g. PostgreSQL, Oracle, T-SQL) this can be done directly using window functions:
select *
from (
select *,
row_number() over (partition by field1 order by field2) as row_number
from table
) as rows
where row_number = 1
On others (MySQL, SQLite), y...
Is Java really slow?
...
Modern Java is one of the fastest languages, even though it is still a memory hog. Java had a reputation for being slow because it used to take a long time for the VM to start up.
If you still think Java is slow, see the benchmarks game re...