Commonly used APIs in an array

The following table shows some commonly used array APIs:

 

The array container supports random access; hence, given an index, the array container can fetch a value with a runtime complexity of O(1) or constant time.

The array container elements can be accessed in a reverse fashion using the reverse iterator:

#include <iostream>
#include <array>
using namespace std;

int main () {

    array<int, 6> a;
    int size = a.size();
    for (int index=0; index < size; ++index)
         a[index] = (index+1) * 100;   

    cout << "\nPrint values in original order ..." << endl;
    
    auto pos = a.begin();
    while ( pos != a.end() )
        cout << *pos++ << "\t";
    cout << endl;

    cout << "\nPrint values in reverse order ..." << endl;
 
    auto rpos = a.rbegin();
    while ( rpos != a.rend() )
    cout << *rpos++ << "\t";
    cout << endl;

    return 0;
}

We will use the following command to get the output:

./a.out

The output is as follows:

Print values in original order ...
100   200   300   400   500   600

Print values in reverse order ...
600   500   400   300   200   100