Error

The error occurs because indexing a Vec returns a value by move, not a reference, so you cannot use that value again in the same scope. Change your code to borrow the element using & or use .get() to access it safely without moving ownership.

let vec = vec![1, 2, 3];
// Instead of: let x = vec[0]; // moves the value
let x = &vec[0]; // borrows the value
println!("Value: {}", x);

If you need to remove the element, use .remove() which returns ownership explicitly:

let mut vec = vec![1, 2, 3];
let x = vec.remove(0); // takes ownership
println!("Removed: {}", x);

The "cannot move out of index of Vec" error happens when you try to take ownership of an item from a list and then use it again, which Rust forbids to prevent memory errors. Think of it like taking a physical book off a shelf; you can't read it at the library if you've already taken it home. You must either borrow the book (read it on the shelf) or explicitly check it out (remove it) to use it elsewhere.