linkedList 7

#include <iostream>

using namespace std;

 class List{
    public:

        List(){ next = NULL; data = 0;}
        int data;
        List* next;
 };

void output (List* x){
   if(x->next != NULL) {
        cout << x->data << " ";
        x = x->next;
        output(x);
    }
    cout << endl;
}

int shift(List*& root, List* head){ // delete one from the end and type data ||-||-/  *5*
    if(root == NULL){
        cout << "I can't do shift. Root is NULL.";
    }else{
        int number = root->data;
        List* node = new List();
        List* x = new List();
        while(head->next->next != NULL){
            head = head->next;
            cout << "test -> " << head->data << " ";
        }
        node = root;
        delete node;
        root = head;
        root->next = NULL;

        return number;
    }
 }

int pop(List*& root, List*& head){
    cout <<  head;
    if(root == NULL){
        cout << "I can't do pop. Root is NULL.";
    }else{
        List* node = new List();
        node = head;

        List* x = new List();
        x = head->next;
        delete node;

        head = x;
        delete x;
    }
    cout <<  head;
    output(head);
}

void unshift (List*& root, int value, List*& head){ // add one list from the beginning |new
    if(root == NULL){
        List* node = new List();
        node->data = value;
        node->next = root;
        root = node;
        cout << root->data << endl;

        head = root;
        //cout << "->";
        //output(head);
        delete node;
    }else{
        List* node = new List();
        node->next = head;
        node->data = value;
        root = node;
        head = node;
        //output(head);
        delete node;
    }
    cout <<  head->data;
}

 void push (List*& root, int value, List*& head){     // insert line to the end ||-||-|new|
    if(root == NULL){
        List *node = new List();
        node->data = value;
        node->next = root;
        root = node;
        //cout << root->data << endl;

        head = root;
        //cout << "->" << " head - data" ;
        output(head);

        delete node;
    }else{
        List *node = new List();
        node->data = value;
        node->next = root;
        root->next = node;
        root = root->next;

        //cout << root->data;
        delete node;
    }

}

 int main(){
    List* head = new List();
    head = NULL;
    List* root = new List();
    root = NULL;
    push(root, 10, head);
    push(root, 20, head);
    //cout << pop(root, head);
    unshift(root, 11, head);
   // output(head);


 }