Let’s do it in two simple lines and without `zeros`

… The first line creates a `n x n`

matrix where all elements are `0`

. After you can (as your hint says) address the elements with a single argument. The distance between the ones in the identity matrix are `n+1`

. This way you write the ones with the mentioned distance until the end.

```
function out = identity(n)
out(n,n) = 0;
out(1:n+1:end) = 1;
end
```