Remove Duplications - Linked List

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

typedef struct Node
{
    char data;
    struct Node* next;
} node;

node* create_node(char data)
{
    node* temp = (node*)malloc(sizeof(node));

    temp->data = data;
    temp->next = NULL;

    return temp;
}

void insert(node** head, char data)
{
    node* temp = *head;
    node* link = create_node(data);

    if (*head == NULL)
    {
        *head = link;
        return;
    }

    while (temp != NULL)
    {
        if (temp->next == NULL)
        {
            temp->next = link;
            return;
        }

        else
            temp = temp->next;
    }
}

void print_list(node* head)
{
    if (head == NULL)
    {
        printf("List is empty\n");
        return;
    }

    node* temp = head;

    while (temp != NULL)
    {
        printf("%c->", temp->data);
        temp = temp->next;
    }

    if (temp == NULL)
        printf("NULL");
}

void remove_duplications(node** head)
{
    // a>a>a>b>b>b>N

    node* i = *head;
    node* j, * temp;

    while (i->next != NULL)
    {
        j = i;

        while (j->next != NULL)
        {
            if (j->next->data == i->data)
            {
                temp = j->next;
                j->next = j->next->next;
                free(temp);
            }

            else if (j->next != NULL)
                j = j->next;
            else
                break;
        }

        if (i->next)
            i = i->next;
        else
            break;
    }
}

void main()
{
    node* head = NULL;

    print_list(head);

    /*insert(&head, 'a');
    insert(&head, 'b');
    insert(&head, 'd');
    insert(&head, 'b');
    insert(&head, 'c');
    insert(&head, 'c');*/

    /*insert(&head, 'a');
    insert(&head, 'a');
    insert(&head, 'b');
    insert(&head, 'b');
    insert(&head, 'c');
    insert(&head, 'a');*/


    insert(&head, 'a');
    insert(&head, 'b');
    insert(&head, 'b');
    insert(&head, 'a');
    insert(&head, 'b');
    insert(&head, 'b');

    /*insert(&head, 'a');
    insert(&head, 'a');
    insert(&head, 'a');
    insert(&head, 'b');
    insert(&head, 'b');
    insert(&head, 'b');*/

    remove_duplications(&head);

    print_list(head);
}