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What is the difference between char array and char pointer in C?
...char* and char[] are different types, but it's not immediately apparent in all cases. This is because arrays decay into pointers, meaning that if an expression of type char[] is provided where one of type char* is expected, the compiler automatically converts the array into a pointer to its first el...
How to set Java environment path in Ubuntu
I just installed JDK in Ubuntu with sudo apt-get install openjdk-6-jdk command,
after the installation where's the Java bin directory located? And how can I set the environment path for that directory? I have little experience with Ubuntu, can anyone give some advice or suggest any good website ...
maximum value of int
...imum value. Same goes for the C macros/constants.
– dalle
Dec 31 '09 at 11:29
4
in C99 you can al...
What's the better (cleaner) way to ignore output in PowerShell? [closed]
...ad and > $null has about a 0.3% overhead.
Addendum 2017-10-16: I originally overlooked another option with Out-Null, the use of the -inputObject parameter. Using this the overhead seems to disappear, however the syntax is different:
Out-Null -inputObject ($(1..1000) | ?{$_ -is [int]})
And no...
ADB Shell Input Events
..."
3 --> "KEYCODE_HOME"
4 --> "KEYCODE_BACK"
5 --> "KEYCODE_CALL"
6 --> "KEYCODE_ENDCALL"
7 --> "KEYCODE_0"
8 --> "KEYCODE_1"
9 --> "KEYCODE_2"
10 --> "KEYCODE_3"
11 --> "KEYCODE_4"
12 --> "KEYCODE_5"
13 --> "KEYCODE_6"
14 --> "KEYCODE_7"
1...
Making a property deserialize but not serialize with json.net
...
There are actually several fairly simple approaches you can use to achieve the result you want.
Let's assume, for example, that you have your classes currently defined like this:
class Config
{
public Fizz ObsoleteSetting { get; set;...
boost::flat_map and its performance compared to map and unordered_map
...e, because your cache will not be warm, and your operation will likely be called just once. Therefore you need to benchmark using RDTSC, and time stuff calling them once only.
Intel has made a paper describing how to use RDTSC (using a cpuid instruction to flush the pipeline, and calling it at least...
How to properly reuse connection to Mongodb across NodeJs application and modules
...lhost:27017";
var _db;
module.exports = {
connectToServer: function( callback ) {
MongoClient.connect( url, { useNewUrlParser: true }, function( err, client ) {
_db = client.db('test_db');
return callback( err );
} );
},
getDb: function() {
return _db;
}
};
To...
Best way to iterate through a Perl array
...ay elements occurs. ($_ is aliased to the element in #1, but #2 and #3 actually copy the scalars from the array.)
#5 might be similar.
In terms memory usage: They're all the same except for #5.
for (@a) is special-cased to avoid flattening the array. The loop iterates over the indexes of the array...
Understanding repr( ) function in Python
...gt;>> x
'foo'
So the name x is attached to 'foo' string. When you call for example repr(x) the interpreter puts 'foo' instead of x and then calls repr('foo').
>>> repr(x)
"'foo'"
>>> x.__repr__()
"'foo'"
repr actually calls a magic method __repr__ of x, which gives the s...