HtmlDiff::FindMatch PHP Метод

    private function FindMatch($startInOld, $endInOld, $startInNew, $endInNew)
    {
        $bestMatchInOld = $startInOld;
        $bestMatchInNew = $startInNew;
        $bestMatchSize = 0;
        $matchLengthAt = array();
        for ($indexInOld = $startInOld; $indexInOld < $endInOld; $indexInOld++) {
            $newMatchLengthAt = array();
            $index = $this->oldWords[$indexInOld];
            if ($this->IsTag($index)) {
                $index = $this->StripTagAttributes($index);
            }
            if (!isset($this->wordIndices[$index])) {
                $matchLengthAt = $newMatchLengthAt;
                continue;
            }
            foreach ($this->wordIndices[$index] as $indexInNew) {
                if ($indexInNew < $startInNew) {
                    continue;
                }
                if ($indexInNew >= $endInNew) {
                    break;
                }
                $newMatchLength = (isset($matchLengthAt[$indexInNew - 1]) ? $matchLengthAt[$indexInNew - 1] : 0) + 1;
                $newMatchLengthAt[$indexInNew] = $newMatchLength;
                if ($newMatchLength > $bestMatchSize) {
                    $bestMatchInOld = $indexInOld - $newMatchLength + 1;
                    $bestMatchInNew = $indexInNew - $newMatchLength + 1;
                    $bestMatchSize = $newMatchLength;
                }
            }
            $matchLengthAt = $newMatchLengthAt;
        }
        return $bestMatchSize != 0 ? new Match($bestMatchInOld, $bestMatchInNew, $bestMatchSize) : null;
    }