Java数据结构之链表相关知识总结

 private class Node{ public E e; public Node next; public Node(E e, Node next){ this.e = e; this.next = next; } public Node(E e){ this(e, null); } public Node(){ this(null,null); } @Override public String toString() { return e.toString(); } } 

 //向链表中间添加元素 //在链表的index(0-based)位置添加新的元素e public void add(int index, E e){ if(index <0 || index> size) throw new IllegalArgumentException("Add failed.Illeagl failed."); Node prev = dummyHead; for (int i = 0; i 

 //链表中删除index(0-based)位置的元素，返回删除的元素 public E remove(int index){ if(index <0 || index>= size) throw new IllegalArgumentException("Remove failed.Illeagl failed."); Node pre = dummyHead; for (int i = 0; i 

 public class LinkedList { private class Node{ public E e; public Node next; public Node(E e, Node next){ this.e = e; this.next = next; } public Node(E e){ this(e, null); } public Node(){ this(null,null); } @Override public String toString() { return e.toString(); } } private Node dummyHead; private int size; public LinkedList(){ dummyHead = new Node(null, null); size = 0; } //获取链表中的元素个数 public int getSize(){ return size; } //返回链表是否为空 public boolean isEmpty(){ return size == 0; } //向链表头添加元素 public void addFirst(E e){ //        Node node = new Node(e); //        node.next = head; //        head = node; add(0, e); } //向链表中间添加元素 //在链表的index(0-based)位置添加新的元素e public void add(int index, E e){ if(index <0 || index> size) throw new IllegalArgumentException("Add failed.Illeagl failed."); Node prev = dummyHead; for (int i = 0; i  size) throw new IllegalArgumentException("Add failed.Illeagl failed."); Node cur = dummyHead.next; for (int i = 0; i  size) throw new IllegalArgumentException("Add failed.Illeagl failed."); Node cur = dummyHead.next; for (int i = 0; i = size) throw new IllegalArgumentException("Remove failed.Illeagl failed."); Node pre = dummyHead; for (int i = 0; i "); //            cur = cur.next; //        } for (Node cur = dummyHead.next; cur != null; cur = cur.next){ res.append(cur + "->"); } res.append("null"); return res.toString(); } public static void main(String[] args) { LinkedList linkedList = new LinkedList<>(); for (int i = 0; i <5; i++) { linkedList.addFirst(i); System.out.println(linkedList); } linkedList.add(2, 666); System.out.println(linkedList); linkedList.remove(2); System.out.println(linkedList); linkedList.removeFirst(); System.out.println(linkedList); linkedList.removeLast(); System.out.println(linkedList); } } 

 public class LinkedListStack implements Stack { private LinkedList list; public LinkedListStack(){ list = new LinkedList<>(); } @Override public int getSize() { return list.getSize(); } @Override public boolean isEmpty() { return list.isEmpty(); } @Override public void push(E value) { list.addFirst(value); } @Override public E pop() { return list.removeFirst(); } @Override public E peek() { return list.getFirst(); } @Override public String toString() { StringBuilder res = new StringBuilder(); res.append("Stack : top"); res.append(list); return res.toString(); } public static void main(String[] args) { LinkedListStack stack = new LinkedListStack<>(); for (int i = 0; i <5; i++) { stack.push(i); System.out.println(stack); } stack.pop(); System.out.println(stack); } } 

 public class LinkedListQueue implements Queue { private class Node{ public E e; public LinkedListQueue.Node next; public Node(E e, LinkedListQueue.Node next){ this.e = e; this.next = next; } public Node(E e){ this(e, null); } public Node(){ this(null,null); } @Override public String toString() { return e.toString(); } } private Node head,tail; private int size; public LinkedListQueue(){ head = null; tail = null; size = 0; } @Override public int getSize() { return size; } @Override public boolean isEmpty() { return size == 0; } @Override public void enqueue(E e) { if(tail == null){ tail = new Node(e); head = tail; }else{ tail.next = new Node(e); tail = tail.next; } size++; } @Override public E dequeue() { if (isEmpty()) throw new IllegalArgumentException("Cannot dequeue form any empty queue."); Node retNode = head; head = head.next; retNode.next = null; if (head == null) tail = null; return retNode.e; } @Override public E getFront() { if (isEmpty()) throw new IllegalArgumentException("Cannot getFront form any empty queue."); return head.e; } @Override public String toString() { StringBuilder res = new StringBuilder(); res.append("Queue : front "); Node cur = head; while (cur != null){ res.append(cur + "->"); cur = cur.next; } res.append("Null tail"); return res.toString(); } public static void main(String[] args) { LinkedListQueue queue = new LinkedListQueue<>(); for (int i = 0; i <10; i++) { queue.enqueue(i); System.out.println(queue); if(i % 3 == 2){ queue.dequeue(); System.out.println(queue); } } } }