How to iterate a Vec<T> with the indexed position?

Question

I need to iterate a Vec including the position for each iterated element. I'm sure this is already in the API but I cannot see it.

I need something like this:

fn main() {
    let v = vec![1; 10];
    for (pos, e) in v.iter() {
        // do something here
    }
}

Pd

Answer 1

You can use the Iterator::enumerate method:

fn main() {
    let v = vec![1; 10];
    for (pos, e) in v.iter().enumerate() {
        println!("Element at position {}: {:?}", pos, e);
    }
}

Playground

Smoker

@Shepmaster Is there also a way to do this and get the element directly instead of a reference to it? – Crispa

@Crispa What is the difference between iter and into_iter? – Quadruplet

if we call .next(), and then enumerate(), it don't keep track of the real index – Cyclone

Answer 2

Not maybe the Rust way but you can try something like:

let n: usize = your_vector.len();

for i in 1..n {
    print!("{}", your_vector[i])
}

Amalburga