C++ now has a **std::filesystem::directory_iterator**, which can be used as

***#include
#include
#include
namespace fs = std::filesystem;

int main() {
std::string path = "/path/to/directory";
for (const auto & entry : fs::directory_iterator(path))
std::cout << entry.path() << std::endl;
}***
Also, **std::filesystem::recursive_directory_iterator** can iterate the subdirectories as well.

You can also try this:

***#include
#include

srand(time(NULL)); // Initialization, should only be called once.
int r = rand(); // Returns a pseudo-random integer between 0 and RAND_MAX.***

We can use **static** as part of an array type declaration as an argument to a function:

***int someFunction(char arg[static 10])
{
...
}***
In this context, this specifies that arguments passed to this function must be an array of type char with at least 10 elements in it.

Ternary is the most convenient way of doing this

******

In C (not C++), you have to declare struct variables like:

**struct myStruct myVariable;**

In order to be able to use myStruct myVariable; instead, you can typedef the struct:

***typedef struct myStruct someStruct;
someStruct myVariable;***

You can combine struct definition and typedefs it in a single statement which declares an anonymous struct and typedefs it.

**typedef struct { ... } myStruct;**

As of version 0.11.0, columns can be sliced in the manner you tried using the **.loc** indexer:

***df.loc[:, 'C':'E']
is equivalent to

df[['C', 'D', 'E']] # or df.loc[:, ['C', 'D', 'E']]***
and returns columns C through E.

We can do this in pandas using **drop**

**df = df.drop('column_name', 1)**

Just assign it to the .columns attribute:

***>>> df = pd.DataFrame({'$a':[1,2], '$b': [10,20]})
>>> df
$a $b
0 1 10
1 2 20

>>> df.columns = ['a', 'b']
>>> df
a b
0 1 10
1 2 20***

You can try this:
**dir & echo foo**

A pseudo environment variable named **errorlevel** stores the exit code:

**echo Exit Code is %errorlevel%**

Also, the **if** command has a special syntax:

**if errorlevel**

#container {
display: flex;
justify-content: center;
align-items: center;
}

:hover is a pseudo-selector and, for CSS, only has meaning within the style sheet. There isn't any inline-style equivalent. So can specify the a:hover property either by using internal CSS or external CSS.