I am trying to figure out why, when I run this code, I am getting undefined for my correct answers.

$(document).ready (function () {
//  

var answers = 
[["Fee","Fi","Fo"], 
["La","Dee","Da"]],
questions = 
["Fee-ing?",
"La-ing?"],
corAns = ["Fee", "La"];

var counter = 0;

var $facts = $('#main_ .facts_div'),
$question = $facts.find('.question'),
$ul = $facts.find('ul'),
$btn = $('.myBtn');


$btn.on('click', function() {
    if (counter < questions.length) {
        $question.text(questions[counter]);

        var ansstring = $.map(answers[counter], function(value) {
            return '<li><input type="radio" name="ans" value="0"/>'
            + value + '</li>'}).join('');
        $ul.html(ansstring);

        var currentAnswers = $('input[name="ans"]:checked').map(function() {
            return this.val();
        }).get();

        var correct = 0;
        if (currentAnswers[counter]==corAns[counter]) {
            correct++;
        }

    }
    else {
        $facts.text('You are done with the quiz ' + correct);
        $(this).hide();
    }
        counter++;
});


//    
});

It is quite long and I'm sorry about that, but I don't really know how tostrip it down.

I also realize this isn't the most elegant way to do this, but I just want to know why I can't seem to get my radio values.

I will add the markup as well if anyone wants.