[1] Beirut Arab Univ, Fac Sci, Beirut, Lebanon
[2] Lebanese Univ, Fac Sci 1, Khawarizmi Lab Math & Applicat KAlMA, Beirut, Lebanon
[3] Univ Fed Rio de Janeiro, NCE, PPGI, Rio de Janeiro, Brazil
[4] Univ Fed Rio de Janeiro, Inst Computacao, Rio de Janeiro, Brazil