How can I avoid circular references with shared_ptr in C++?

How can I avoid circular references with shared_ptr in C++?

To avoid circular references with shared_ptr, you can use weak_ptr for one of the references. This breaks the cycle.

Can you give me an example of how to implement weak_ptr?

Sure! Here's a simple example:

#include <iostream>
#include <memory>

class Node {
public:
    std::shared_ptr<Node> next;
    std::weak_ptr<Node> prev;
};

int main() {
    auto node1 = std::make_shared<Node>();
    auto node2 = std::make_shared<Node>();
    node1->next = node2;
    node2->prev = node1; // Use weak_ptr to avoid circular reference
}

What happens if I don't use weak_ptr?

If you don't use weak_ptr, both shared_ptr instances will keep each other alive, leading to a memory leak because neither can be destroyed.

Are there any other strategies to manage memory in C++?

Yes, you can also use unique_ptr for exclusive ownership, or consider using smart pointers in combination with RAII principles.