#include <mutex>

class Node { 
    protected:
        int data; 
        bool is_dummy;
        std::mutex mut;

    public:
        Node* next;
        bool deleted;

        Node(int element);
        static Node* Dummy();
        //  Dummy();

        void lock();
        void unlock();
        bool is_smaller_than(int n);
        bool is_smaller_than(Node* n);
        bool is_equal(int n);
};


Node::Node(int element){
    data = element;
    is_dummy = false;
    deleted = false;
}

Node* Node::Dummy(){
    Node* n = new Node(0);
    n->is_dummy = true;
    return n;
}

bool Node::is_smaller_than(Node* n) {
    return this->is_smaller_than(n->data);
}

bool Node::is_smaller_than(int n) {
    // Everything is smaller than a dummy -> false
    return  this->data < n && !this->is_dummy;
}

bool Node::is_equal(int n) {
    // Dummies are not equal to any number -> false
    return  this->data == n && !this->is_dummy;
}

void Node::lock() {
    this->mut.lock();
} 
void Node::unlock() {
    this->mut.unlock();
}