study case for shared_pointers. a shared_ptr<T> will destroy itself when there is no more references to it acting as a garbage collector

shared_pointer.cpp

#include <iostream>
#include <memory>

using namespace std;

shared_ptr<int> create_new_number()
{
    return shared_ptr<int>(new int(90));
}

template<class T>
void increment_number(T number)
{
    (*number)++;
}

template<class T>
void sum_by(T number, int value)
{
    *number += value;
}

int main()
{
    auto foo = create_new_number();
    cout << "initial value: " << *foo << '\n';
    increment_number(foo);
    cout << "incremented value: " << *foo << '\n';
    sum_by(foo, 35);
    cout << "added 35 to number: " << *foo << '\n';

}