JS Digital Root

digitalroot.js

function root(num){
    var total = 0;
    if(num.toString().length == 1){
        var iNum = parseInt(num);
        return iNum;
    }else{
        num.toString().split("").forEach( function(value){
            var iValue = parseInt(value);
            return total += iValue;
        });
        return root(total);
    }
}

function digitalRoot(n) {
return n % 9;
}
that's it