Get last element from vector

I have this simple piece of code:

fn main() {
    let mut blockchain: Vec<blockchain::Block> = Vec::new();

    let genesis_block = blockchain::create_block("genesis_block");

    blockchain::add_block_to_blockchain(&mut blockchain, genesis_block);
}

My error occurs here:

pub fn get_last_block(blockchain: &Vec<Block>) -> Block {
    return blockchain[blockchain.len() - 1];
}

It says:

I am pretty new to rust, so can somebody explain me why this wont work?

I just trying to get the last element of this vector.

Should i pass the ownership of this vector instead of borrowing it?

EDIT: This is my result now:

pub fn get_last_block(blockchain: &Vec<Block>) -> Option<&Block> {
    return blockchain.last();
}

blockchain could be empty. I check with is_some if its returning an value

let block = blockchain::get_last_block(&blockchain);
if block.is_some() {
    blockchain::print_block(block.unwrap());
}

>Solution :

Since you are borrowing the vector, you can either:

• return a reference to the block
• clone the block
• pop the block from the vec and return it (you would need to mutably borrow it instead, &mut)

Also, consider using an Option as return type, in case your vector is empty. By using this, you could directly call to last for example, this would return a reference & to the last Block:

pub fn get_last_block(blockchain: &Vec<Block>) -> Option<&Block> {
    blockchain.last()
}

Nitpick, you could use a slice instead of a Vec in the function signature:

fn get_last_block(blockchain: &[Block])...