sur->mac

2026-05-11 17:35:58 +02:00
parent 29ef5b6655
commit e4d2eb3ab8
1264 changed files with 30997 additions and 136657 deletions
@@ -0,0 +1,183 @@
+package list.mylinkedlist;
+
+import java.util.List;
+import java.util.NoSuchElementException;
+
+public class MyLinkedList<E> implements List<E> {
+		
+	/*
+	 * Classe Nodo
+	 */
+	private static class Node<E> {
+		
+		// Dati del nodo
+		private E data;
+		
+		// Riferimenti elemento precedente e successivo
+		private Node<E> prev;
+		private Node<E> next;
+		
+		// Costruttore
+		public Node(E data, Node<E> prev, Node<E> next) {
+			this.data = data;
+			this.prev = prev;
+			this.next = next;
+		}
+		
+	}
+	
+	private Node<E> head = null;
+	private Node<E> tail = null;
+	private int size = 0;
+	
+	// Costruttore
+	public MyLinkedList() {}
+	
+	// Metodi
+	
+	public boolean isEmpty() {
+		return size == 0;
+	}
+	
+	public int size() {
+		return size;
+	}
+	
+	public E getFirst() {
+		if (head == null) throw new NullPointerException();
+		return head.data;
+	}
+	
+	public void addFirst(E item) {
+		if (item == null) throw new NullPointerException();
+		Node<E> newNode = new Node<E>(item, null, null);
+		if (size == 0) {
+			head = tail = newNode;
+		} else {
+			head.prev = newNode;
+			newNode.next = head;
+			head = newNode;
+		}
+		size++;
+	}
+	
+	public E removeFirst() {
+		if (head == null) throw new NoSuchElementException();
+		E tmp = head.data;
+		if (size == 1) {
+			head = tail = null;
+		} else {
+			Node<E> firstPlace = head;
+			Node<E> secondPlace = head.next;
+			
+			head = secondPlace;
+			secondPlace.prev = null;
+			firstPlace.next = null;
+		}
+		size--;
+		return tmp;
+	}
+	
+	public E getLast() {
+		if (tail == null) throw new NullPointerException();
+		return tail.data;
+	}
+	
+	public E removeLast() {
+		if (tail == null) throw new NoSuchElementException();
+		E tmp = tail.data;
+		if (size == 1) {
+			head = tail = null;
+		} else {
+			Node<E> lastNode = tail;
+			Node<E> penultimateNode = tail.prev;
+			
+			tail = penultimateNode;
+			penultimateNode.next = null;
+			lastNode.prev = null;
+		}
+		size--;
+		return tmp;
+	}
+	
+	public void addLast(E item) {
+		if (item == null) throw new NullPointerException();
+		Node<E> newNode = new Node<E>(item, null, null);
+		if (size == 0) {
+			head = tail = newNode;
+		} else {
+			Node<E> oldLastNode = tail;
+			oldLastNode.next = newNode;
+			newNode.prev = oldLastNode;
+			tail = newNode;
+		}
+		size++;
+	}
+	
+	public void clear() {
+		head = tail = null;
+		size = 0;
+	}
+	
+	public boolean add(E item) {
+		if (item == null) throw new NoSuchElementException();
+		addLast(item);
+		return true;
+	}
+	
+	public void add(int index, E item) {
+		if (item == null) throw new NullPointerException();
+		if (index < 0 || index > size) throw new IndexOutOfBoundsException();
+		// Se l'inserimento è richiesto nella prima posizione
+		if (index == 0) {
+			addFirst(item);
+			return;
+		}
+		// Se l'inserimento è richiesto nell'ultima posizione
+		if (index == size) {
+			addLast(item);
+			return;
+		}
+		// Se l'inserimento è richiesto nel generico posto i
+		Node<E> newNode = new Node<E>(item, null, null);
+		
+		Node<E> prevNode = head;
+		for (int i = 0; i < index - 1; i++) {
+			prevNode = prevNode.next;
+		}
+		
+		Node<E> nextNode = prevNode.next;
+		
+		prevNode.next = newNode;
+		newNode.prev = prevNode;
+		newNode.next = nextNode;
+		nextNode.prev = newNode;
+		
+		size++;
+	}
+	
+	public E get(int index) {
+		if (index < 0 || index >= size) throw new IndexOutOfBoundsException();
+		
+		Node<E> currentNode = head;
+		for (int i = 0; i < index; i++) {
+			currentNode = currentNode.next;
+		}
+		return currentNode.data;
+	}
+	
+	public E set(int index, E item) {
+		if (index < 0 || index >= size) throw new IndexOutOfBoundsException();
+		
+		Node<E> currentNode = head;
+		for (int i = 0; i < index; i++) {
+			currentNode = currentNode.next;
+		}
+		E oldData = currentNode.data;
+		currentNode.data = item;
+		return oldData;
+	}
+	
+
+	
+}