Use Bracket Notation to Find the NthtoLast Character in a String (Not sure why it isn't working?)

Tell us what’s happening:

Your code so far

// Example
var firstName = "Ada";
var thirdToLastLetterOfFirstName = firstName[firstName.length - 3];

// Setup
var lastName = "Lovelace";

// Only change code below this line
var secondToLastLetterOfLastName = lastName[firstName.length - 5];

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Link to the challenge:

You should use the length of lastName, not of firstName.

I understand now! Oh dear - pardon my algorithm reading

well you see it starts at 0 so
L o v elace
^ ^ ^
012
then we know that

var secondLetterOfFirstName = firstName[1];

but only need to alter it to last name so it becomes:

var thirdLetterOfLastName = lastName[2];