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  • This session has been presented March 19, 2004.

Description

  • Speaker

    Sidi Mohamed Sedeljmaci

Nous présentons un nouvel algorithme itératif pour le PGCD de deux entiers ou deux polynômes. Il est base sur une procédure itérative de type half-GCD qui évite la répétition d'appels récursifs. On procède progressivement a partir des bits de poids les plus forts. Quoique la complexité reste en $O(n \log2 n \log \log n$ pour deux entiers de $n$ bits, comme l'algorithme fameux de Schonhage, notre algorithme réduit la taille des entiers d'au moins un demi mot mémoire a chaque itération. La simplicité de son schéma algorithmique pourrait en faire une alternative utile aux algorithmes récursifs du PGCD.

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