var currentElement = null;
$('input[name="option[346]"]:radio').on('change', function() {
if (currentElement) currentElement.removeClass('checked');
currentElement = $(this).closest('li').addClass('checked');
});
var someObject = {numSides:3};
var outputNumSides = function() {
var obj = prompt('asd');
return window[obj].numSides;
}
document.write(outputNumSides());