use std::rc::Rc;

fn main() {
    // Create an Rc<String> which holds ownership of "hello, Rust!"
    let s1 = Rc::new(String::from("hello, Rust!"));
    println!("Reference count for s1: {}", Rc::strong_count(&s1)); // Output: 1

    // Create a new Rc that shares ownership with s1
    let s2 = Rc::clone(&s1); // This increments the reference count
    println!("Reference count for s1 (after s2): {}", Rc::strong_count(&s1)); // Output: 2

    {
        // Another Rc clone, demonstrating how counts change
        let s3 = Rc::clone(&s1);
        println!("Reference count for s1 (after s3): {}", Rc::strong_count(&s1)); // Output: 3
        // s3 goes out of scope here, reference count decreases
    }

    println!("Reference count for s1 (after s3 drop): {}", Rc::strong_count(&s1)); // Output: 2

    // Both s1 and s2 still valid
    println!("s1: {}", s1);
    println!("s2: {}", s2);

    // When s1 and s2 go out of scope, the data "hello, Rust!" will be deallocated
    // only when the last Rc pointer owning it is dropped.
}