void (*delete)(struct _cstack_t *self);
} cstack_t;
cstack_t *cstack_init();
void cstack_push(cstack_t *self, char c);
char cstack_pop(cstack_t *self);
void (*delete)(struct _cstack_t *self);
} cstack_t;
cstack_t *cstack_init();
void cstack_push(cstack_t *self, char c);
char cstack_pop(cstack_t *self);