SinglyLinkedList.cpp

#include <iostream>
#include <stdexcept>

using namespace std;

class SinglyLinkedList {
   private:
    class Node {
       public:
        Node* next;
        char data;

        Node(char data, Node* next) {
            this->data = data;
            this->next = next;
        }
    };

    Node* head;
    int length;

   public:
    SinglyLinkedList() {
        this->head = nullptr;
        this->length = 0;
    }

    ~SinglyLinkedList() {
        Node* no = this->head;
        while (no != nullptr) {
          Node* noNext = no->next;
          delete no; //eyðum hnút
          no = noNext; //sækjum næsta
        }

        cout << "Kallað hefur verið á eyðinn fyrir listann" << endl;
    }

    int size() { return this->length; }

    void display() {
        for (Node* node = this->head; node != nullptr; node = node->next) {
            cout << node->data << " -> ";
        }
        cout << "Ø" << endl;
    }

    void prepend(char c) {
        Node* pre = new Node(c, this->head); //ný hnútur sem vísar á haus
        this->head = pre; //þessi punktur verður hausinn
        this->length++;
    }

    char operator[](int n) {
        if (n < this->length) {

          Node* no = this->head;
          for (int i=0; i<n; i++) { //flökkum n sinnum um listann
            no = no->next;
          }
          return no->data; //skilum gögnunum sem n-ti hnúturinn inniheldur

        } else {
          //ef n er útfyrir lengd listans (semsagt jafntog eða stærri):
          throw out_of_range("Index out of range");
        }
    }
};

int main() {
    // Skilgreining lista sem inniheldur tákn
    SinglyLinkedList list;
    list.prepend('G');
    list.prepend('3');
    list.prepend('0');
    list.prepend('2');
    list.prepend('L');
    list.prepend('O');
    list.prepend('T');

    list.display();

    cout << "Stak 0 í listanum er " << list[0] << endl;
    cout << "Stak 3 í listanum er " << list[3] << endl;

    return 0;
}