function cleanDirty(arr) {
    	var tmp = [];
    	for(var i = 0, j = arr.length; i < j; i++) {
    		arr[i] && tmp.push(arr[i]);
    	}
    	return tmp;
    }
[cleanDirty description]
@param  {[type]} arr [description]
@return {[type]}     [description]