Array.prototype.remove = function(p){
	for (var i = 0; i < this.length; i++){
		if (p == this[i]){
			this.splice(i, 1);
			break;
		}
	}
}

Array.prototype.contains = function(p){
	for (var i = 0; i < this.length; i++){
		if (p == this[i]){
			return true;
		}
	}
	return false;
}