#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>

typedef struct list_t
{
    uint8_t  data;
    struct list_t *next;
} list_t;

void list_init(struct list_t *list)
{
    list->data = 0;
    list->next = NULL;
}

void list_add(struct list_t *list, uint8_t data)
{
    struct list_t *p = NULL;
    p = list;
    while (p->next != NULL)
    {
        p = p->next;
        if (p->data == data)
        {
            return;
        }
    }
    p->next = (struct list_t *)malloc(sizeof(struct list_t));
    p->next->data = data;
    p->next->next = NULL;
    return;
}

void list_print(struct list_t *list)
{
    struct list_t *p = NULL;
    p = list;
    while (p->next != NULL)
    {
        printf("%02d\n", p->data);
        p = p->next;
        if (p->next == NULL)
        {
            printf("%02d\n", p->data);
            break;
        }
    }
}

void list_free(struct list_t *list)
{
    struct list_t *p = NULL;
    p = list;
    while (p->next != NULL)
    {
        p = p->next;
        free(p->next);
        p->next = NULL;
        if (p->next == NULL)
        {
            break;
        }
    }
}


void list_demo(void)
{
    struct list_t list;
    list_init(&list);
    for(uint32_t i = 0; i < 10; ++i)
    {
        list_add(&list, i);
    }
    list_print(&list);
}


void main(int arg, char *argv[])
{
#if 0
    uint32_t i = 0;
    for (i = 0; i < 10; ++i)
    {
        printf("%02d\n", i);
    }
    printf("\n");
    
    printf("Hello World!\n");
#else
    // struct list_t list;
    // list_init(&list);
    // list_add(&list, 1);
    // list_add(&list, 2);
    // list_add(&list, 3);
    // list_add(&list, 4);

    // list_print(&list);

    list_demo();
#endif
}