fn change_third(slice: &mut [u32]) { if let Some(item) = slice.get_mut(2) { *item += 1 } } fn print_third(slice: &[u32]) { if let Some(item) = slice.get(2) { println!("Third element: {}", item); } } fn main() { let mut my_vector = vec![73, 55, 33]; print_third(&my_vector); change_third(&mut my_vector[..]); print_third(&my_vector); }