#include <stdlib.h>
/*
 * Compile time polymorphic vector implementation
 */
#define VECTOR_GEN(T)                                                          \
    struct vector_##T;                                                     \
    /*                                                                     \
     * vmethod table                                                       \
     */                                                                    \
    struct vec_v_table_##T {                                               \
        void (*free_vec)(struct vector_##T *);                         \
        void (*push_back)(struct vector_##T *, T const);               \
        T *(*at)(struct vector_##T *, size_t i);                       \
        T *(*front)(struct vector_##T *);                              \
        T *(*back)(struct vector_##T *);                               \
    };                                                                     \
    /*                                                                     \
     * vector struct                                                       \
     */                                                                    \
    struct vector_##T {                                                    \
        size_t capacity;                                               \
        size_t size;                                                   \
        T *data;                                                       \
        struct vec_v_table_##T *m;                                     \
    };                                                                     \
    /*                                                                     \
     * memory related methods                                              \
     */                                                                    \
    void free_v_##T(struct vector_##T *self) { free(self->data); }         \
                                                                               \
    void resize_v_##T(struct vector_##T *self)                             \
    {                                                                      \
        if (self->capacity == 0) {                                     \
            self->capacity = 1;                                    \
                                                                               \
            self->data = malloc(sizeof(T));                        \
        } else {                                                       \
            self->capacity *= 2;                                   \
                                                                               \
            self->data =                                           \
                realloc(self->data, self->capacity * sizeof(T));   \
        }                                                              \
                                                                               \
        if (self->data == NULL) {                                      \
            puts("Error (re)allocating memory");                   \
            exit(1);                                               \
        }                                                              \
    }                                                                      \
                                                                               \
    void push_back_v_##T(struct vector_##T *self, T const elem)            \
    {                                                                      \
        if (self->capacity == self->size)                              \
            resize_v_##T(self);                                    \
                                                                               \
        self->data[self->size] = elem;                                 \
        self->size++;                                                  \
    }                                                                      \
    /*                                                                     \
     * index methods                                                       \
     */                                                                    \
    T *at_v_##T(struct vector_##T *self, size_t i)                         \
    {                                                                      \
        if (i >= self->size) {                                         \
            puts("Error out of bounds");                           \
            exit(1);                                               \
        }                                                              \
                                                                               \
        return &self->data[i];                                         \
    }                                                                      \
                                                                               \
    T *front_v_##T(struct vector_##T *self)                                \
    {                                                                      \
        return self->m->at(self, 0);                                   \
    }                                                                      \
                                                                               \
    T *back_v_##T(struct vector_##T *self)                                 \
    {                                                                      \
        return self->m->at(self, self->size - 1);                      \
    }                                                                      \
    /*                                                                     \
     *  Initialize v table                                                 \
     */                                                                    \
    struct vec_v_table_##T vec_v_t_##T = {                                 \
        free_v_##T, push_back_v_##T, at_v_##T, front_v_##T, back_v_##T};   \
    /*                                                                     \
     * vector init                                                         \
     */                                                                    \
    void init_vec_##T(struct vector_##T *self)                             \
    {                                                                      \
        self->m        = &vec_v_t_##T;                                 \
        self->capacity = 0;                                            \
        self->size     = 0;                                            \
    }