Compilare: user.c: In function ‘add_key’: user.c:465:2: warning: implicit declaration of function ‘strdup’ [-Wimplicit-function-declaration] h->chei[h->n_chei++] = strdup(s); ^ user.c:465:23: warning: assignment makes pointer from integer without a cast [enabled by default] h->chei[h->n_chei++] = strdup(s); ^ user.c: In function ‘add_val’: user.c:482:27: warning: assignment makes pointer from integer without a cast [enabled by default] h->valori[h->n_valori++] = strdup(s); ^