public function preprocess( $pSaxReferenceString, array $pSaxAnalysisStrings) {
        $this->referenceSuffixTree = new SuffixTree( $pSaxReferenceString );

        foreach ( $pSaxAnalysisStrings as $anaString ) {
            $anaTree = new SuffixTree($anaString);
            $this->annotateSurpriseValues( $this->referenceSuffixTree, $anaTree );
            $this->analysisSuffixTree[] = $anaTree;
        }
        
        return $this->analysisSuffixTree;
    }