Declaring a shared Pointer within a function produce a leaky memory behavior - pointers

Question

I‘ve been trying to understand smart pointers, and as I understood, smart pointer will destroy themselves once they are not reachable through the code.
For this reason I was trying to implement a demonstration for this behavior:
#include<iostream>
#include<memory>
using namespace std;
void shared(){
cout<<"Shared Pointer:"<<endl;
shared_ptr<int> number = make_shared<int>(50);
cout<<*number<<endl;
cout<<number<<endl;
}
int main(){
int address;
shared();
cout<<"please enter the targeted address:"<<endl;
cin>>address;
int *pointer = (int *) address;
cout<<"we found this number: "<<*pointer<<endl;
}
output:
Shared Pointer:
50
0xf28c30
please enter the targeted address:
15895600 // I just converted the hexdecimal above to decimal number.
we found this number: 50
So I‘m able to retrieve the value 50 from outside the function shared(), by manually entering its address in the console.
Isn‘t supposed to be null or random number? If this is normal then how smartpointers are made to avoid memory leaks!?
P.S: doing the same test using a normal pointer will produce the same results unless we add delete pointer; (which is the expected behavior)
I appreciate any idea about this specific behavior.

Answer 1

To make sure that the memory was deleted it is better to test the smart pointers with a class
class Greeting {
public:
Greeting()
{
std::cout << "Hello" << std::endl;
}
~Greeting()
{
std::cout << "Bye" << std::endl;
}
};
void shared() {
shared_ptr<Greeting> var = make_shared<Greeting>();
}
int main() {
std::cout << "Start" << std::endl;
shared();
std::cout << "End" << std::endl;
}
You will get the following output:
Start //Start of the main
Hello // When creating the object (the resource)
Bye // **When destructing the object (the resource)**
End //End the main