public function sentinelSearch($value){
		
		$l = $this->count();
		$arr = $this->_Arr;
		$arr[$l] = $value;
		$i = 0;
		
		while($arr[$i] !== $value){
			++$i;
		}
		
		return $i !== $l ? $i : static::NO_INDEX;
		
	}