Array.prototype.unique = function() {
  	var result = [];
  	for (var i = 0; i < this.length; i++) {
  		for (var j = i + 1; j < this.length; j++) {
  			if (this[i] === this[j])
  				j = ++i;
  		}
  		result.push(this[i]);
  	}
  	return (result);
  };