class Tampon:
    def __init__(self, capacite):
        self.capacite = capacite
        self.contenu = [None for i in range(capacite)]
        self.debut = 0 # Indice de la tête de file
        self.fin = 0   # Indice de la queue de file exclu

    def ajouter_element(self, element):
        self.contenu[self.fin] = element
        self.fin = self.fin + 1
        if self.fin == self.capacite:
            self.fin = 0

    def retirer_element(self):
        res = self.contenu[self.debut]
        self.debut = self.debut + 1
        if self.debut == self.capacite:
            self.debut = 0
        return res

    def est_vide(self):
        return self.debut == self.fin

memoire = Tampon(5)
memoire.ajouter_element('n')
memoire.ajouter_element('s')
memoire.ajouter_element('i')
memoire.retirer_element()
memoire.ajouter_element('n')
memoire.ajouter_element('f')
memoire.retirer_element()
memoire.ajouter_element('o')
print(memoire.contenu)