exos_dl_init.mws Exercice 3 Exercice 7 Exercice 13 Exercice 14 Exercice 15 Exercice 16 Exercice 17 Exercice 20 un peu plus subtil Exercice 21 Exercice 22 22.1 22.2 22.3 22.4 Exercice 23 Exercice 24