Linked List in C++

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#include <iostream>

using namespace std;

class Node
{
public:
    int num;
    class Node *next;

    Node()
    {
        num = 0;
        next = nullptr;
    }

    Node(int val)
    {
        num = val;
        next = nullptr;
    }
};

class linked_list
{
    Node* head;
    Node* create_node(int val);
public:
    linked_list()
    {
        head = nullptr;
    }
    // insert at the end of the list
    void insert_node(int val); 
    void delete_node(int val);
    void reverse_list();
    bool is_list_cycle();
    void print_list();
};

Node* linked_list::create_node(int val)
{
   Node* new_node = new Node(val);
   return new_node;
}

void linked_list::insert_node(int val)
{
   Node* current = head;
   if (current == nullptr)
   {
       current = create_node(val);
       head = current;
       //cout << current->num << " inserted into the list as head\n";
       return;
   }
   else {
       while (current->next != nullptr)
       {
          current = current->next;
       }
       current->next = create_node(val);
   }
}

void linked_list::delete_node(int val)
{
    Node* current = head;
    Node* prev;
    while(current != nullptr)
    {
        if(current->num == val)
        {
           if (current == head)
           {
               head = current->next;
           } 
           else {
               prev->next = current->next;
           }
           delete current;
           break;
        }
        else {
           prev = current;
           current = current->next;
        } 
    }
}

// 206. Reverse Linked list (75 Blind Leetcode)
void linked_list::reverse_list()
{
    Node* current = head;
    Node* prev = nullptr;
    while(current != nullptr)
    {
        Node* tmp = current->next;
        current->next = prev;
        prev = current;
        current = tmp;
    }
    head = prev;
}

// 141. Linked list cycle
bool linked_list::is_list_cycle()
{
   Node* slow = head; // Shifts one step 
   Node* fast = head; // Shifts two steps

   while (fast != nullptr && fast->next != nullptr)
   {
       slow = slow->next;
       fast = fast->next->next;

       if (slow == fast) 
       {
         return true;
       }
   }
   return false;
}

void linked_list::print_list()
{
    Node* current = head;
    cout << "The current list:\n";
    while(current != nullptr)
    {
       cout << current->num << " ";
       current = current->next;
    }
    cout << "\n\n";
}

int main()
{
    linked_list list;

    // Insert Head Node
    list.insert_node(5);
    list.print_list();

    // Insert nodes at the end of the list
    list.insert_node(8);
    list.insert_node(10);
    list.insert_node(2);
    list.print_list();

    // Delete the node
    list.delete_node(8);
    list.print_list();
    
    list.insert_node(15);
    list.print_list();

    // Reverse the list
    list.reverse_list();
    list.print_list();

    // detect if list is a cycle
    if (list.is_list_cycle())
    {
        cout << "Cycle is detected in the list\n";
    } else {
        cout << "No cycle in the list";
    }

    return 0;
}

Output:

The current list: 5 The current list: 5 8 10 2 The current list: 5 10 2 The current list: 5 10 2 15 The current list: 15 2 10 5 No cycle in the list