Simple Linked List

Here we’re demonstrates a simple linked list.

The only operations allowed in this version of a list are:

Inserting an item at the beginning of the list
Deleting the item at the beginning of the list
Iterating through the list to display its contents

These operations are fairly easy to carry out, so we’ll start with them.

$ dart 04_linked_list/linked_list/simple_linked_list.dart

import 'dart:io';

class Link {
  int intData;
  double doubleData;
  Link next;

  Link(int id, double dd) {
    intData = id;
    doubleData = dd;
    next = null;
  }

  void displayLink() {
    stdout.write('{ $intData, $doubleData } ');
  }
}

class LinkList {
  Link first;
  
  LinkList() {
    first = null;
  }

  bool isEmpty() {
    return first == null;
  }

  void insertFirst(int id, double dd) {
    Link newLink = new Link(id, dd);
    newLink.next = first;
    first = newLink;
  }

  Link deleteFirst() {
    Link temp = first;
    first = first.next;
    return temp;
  }

  void displayList() {
    stdout.write('List frist -> last ');
    Link curent = first;
    while(curent != null) {
      curent.displayLink();
      curent = curent.next;
    }
    stdout.writeln();
  }
}

void main() {
  LinkList linkList = new LinkList();  // Создание нового списка
  linkList.insertFirst(22, 2.99);
  linkList.insertFirst(44, 4.99);
  linkList.insertFirst(66, 6.99);
  linkList.insertFirst(88, 8.99);

  linkList.displayList();

  while(!linkList.isEmpty()) {
    Link tempLink = linkList.deleteFirst();
    stdout.write('Deleted');
    tempLink.displayLink();
    stdout.writeln();
  }
  linkList.displayList();
}