array basics in JavaScript

What this snippet does

at() accepts negative indices as a clean alternative to arr[arr.length - n] for accessing from the end.

Expected output

5
10
50
50
40
true

Why practise typing this

Typing arrays code builds muscle memory for the symbols and indentation JavaScript uses most, which prose-based typing tests never cover. DevType measures your words per minute and accuracy on this snippet and tracks the individual characters you mistype, so later lessons can target them.

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