$.fn.preload = function() {
    this.each(function(){
        $('<img/>')[0].src = this;
    });
}

$([
    '/images/npc.jpg',
    '/images/wtitd.jpg',
    '/images/mct.jpg',
    '/images/path.jpg',
    '/images/path-about.jpg',
    '/images/path-mission.jpg',
    '/images/path-newsletter.jpg',
    '/images/path-resources.jpg',
    '/images/path-services.jpg',
    '/images/about_01.jpg',
    '/images/tony_bonnie_01.jpg'
]).preload();

$(document).ready(function() {
    var loc = window.location.pathname;
    var index = loc.lastIndexOf("/");
    var fileName = loc.substr(index + 1);
    var key = fileName.replace(/\.html/, "");

    if (!key) {
        $("#index").addClass("menu-current");
    } else {
        $("#" + key).addClass("menu-current");
    }
});