Array.prototype.find = function(search) {
    var k = this.length;
    while (k--) if (this[k]===search) return true;
    k = null;
    return false;
}

function hasClass(element, className) {
    var tmpClass = element.className.split(" ");
    return tmpClass.find(className);
}

function addClass(element, className) {
    var tmpClass = element.className.split(" ");
    if (!tmpClass.find(className)) {
        tmpClass.push(className);
        element.className = tmpClass.join(" ");
    }
    tmpClass = null;
}



function removeClass(element, className){
    var tmpClass = element.className.split(" ");
    var newClass = "";
    var k = tmpClass.length;
    while (k--) if (tmpClass[k]!=className) newClass+= tmpClass[k]+" ";
    element.className = newClass;
    tmpClass = newClass = k = null;
}