Another_RK_3

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <string.h>

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

void AddNode(Node*& first, char symbol)
{
    if (first == NULL)
    {
        first = new Node;
        first->data = symbol;
        first->next = NULL;
    }
    else
    {
        Node* cur = first;
        first = new Node;
        first->data = symbol;
        first->next = cur;
    }
}

void PrintList(Node* first)
{
    while (first != NULL)
    {
        printf("%c ", first->data);
        first = first->next;
    }
}

void ClearMemory(Node*& first)
{
    while (first != NULL)
    {
        Node* tmp = first;
        first = first->next;
        delete tmp;
    }
}

void InsertNodeAfter(Node*& cur, char symbol)
{
    Node* new_node = new Node;
    new_node->data = symbol;
    new_node->next = cur->next;
    cur->next = new_node;
}

void InsertHash(Node* first)
{
    int cnt = 0;
    while (first->next != NULL)
    {
        cnt++;
        if (cnt % 2 != 0)
        {
            InsertNodeAfter(first, '#');
            first = first->next;
        }
        first = first->next;
    }
}

void DeleteNodeAfter(Node*& cur)
{
    Node* tmp = cur->next;
    cur->next = tmp->next;
    delete tmp;
}

void DeleteSymbols(Node* first)
{
    int cnt = 0;
    while (first->next != NULL)
    {
        cnt++;
        if ((cnt+1) % 3 == 0)
        {
            DeleteNodeAfter(first);
            cnt++;
        }
        if (first->next != NULL)
            first = first->next;
    }
}

int main()
{
    Node* first = NULL;
    char str[80];
    char* ptr;

    puts("Enter the word sequence without spaces:");
    gets_s(str);
    for (int i = 0; i < strlen(str); i++)
        AddNode(first, str[i]);
    puts("\nThe formed list:");
    PrintList(first);
    DeleteSymbols(first);
    puts("\nThe formed list:");
    PrintList(first);
    ClearMemory(first);
    puts("\n");
    return 0;
}