P.03

JAVA 实现一个链表

 

class Node {
	public int data;
	public Node next;

	public Node() {
		data = 0;
		next = null;
	}

	public Node(int d, Node n) {
		data = d;
		next = n;
	}

	public void setData(int data) {
		this.data = data;
	}

	public void setNext(Node next) {
		this.next = next;
	}

	Node getNext() {
		return next;
	}

	int getData() {
		return data;
	}
}

class LinkList {
	private Node head, end, current;

	LinkList() {
		head = end = current = null;
	}

	void print() {
		if (head == null) {
			System.out.println("The list is empty!");
			System.exit(0);
		} else {
			current = head;
			while (current != null) {
				System.out.print(current.data + " ");
				current = current.next;
			}
		}
	}

	void insertTail(int d) {
		Node newnode = new Node(d, null);
		if (head == null) {
			head = newnode;
			end = newnode;
			newnode.next = null;
		} else {
			end.next = newnode;
			end = newnode;
			end.next = null;
		}
	}

	void insertHead(int d) {
		Node newnode = new Node(d, null);
		if (head == null) {
			head = newnode;
			end = newnode;
			newnode.next = null;
		} else {
			newnode.next = head;
			head = newnode;
		}
	}

	int length() {
		if (head == null)
			return 0;
		else {
			int len = 0;
			current = head;
			while (current != null) {
				len++;
				current = current.next;
			}
			return len;
		}
	}

	int search(int d) {
		int index;
		if (head == null) {
			System.out.println("Search in a empty list is illeagal!");
			System.exit(1);
		} else {
			index = 0;
			current = head;
			while (current != null) {
				index++;
				if (current.data == d)
					break;
				current = current.next;
			}
			if(current != null)
				return index;
		}
		return -1;
	}

	public static void main(String args[]) {
		LinkList one = new LinkList();
		for (int i = 10; i < 20; i++)
			one.insertTail(i);
		one.print();
		System.out.println();
		System.out.println(one.search(16));
		
	}

}