java单链表基础

package dataStructure;

/**
 * 结点类，进行结点内容的保存
 * @author
 */
public class Node {
	public Object data;        //存放结点
	public Node next;             //后继结点
	
	public Node() {
		this(0, null);
	}
	public Node(Object num) {
		this(num, null);
	}
	public Node(Object num, Node next) {
		this.data = num;
		this.next = next;
	}

}
package dataStructure;


import java.util.Scanner;


public class LinkList {
	private Scanner input = new Scanner(System.in);
	public Node head;         //头结点
	
	public LinkList() {         //单链表构造方法
		head = new Node();    //初始化头结点
	}
	public LinkList(int num, boolean Order) {     //构造一个长度为n的单链表
		this();    //初始化头结点
		
			try {
				if( Order )
					createOfTial( num );
				else
					createOfHead( num );//头插法
			} catch (Exception e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
	}
	private void createOfHead(int num) throws Exception{
		int i = 0;
		for(i = 0; i < num; i++){
			insert(lenght(), input.next());
		}
		
	}
	public void createOfTial(int num ) throws Exception{
		int i = 0;
		for(i = 0; i < num; i++){
			insert(lenght(), input.next());
		}
	}
	public void clear(){//清空链表
		head.next = null;
		head.data = null;
	}
	public boolean isEmpty(){     //判断带头节点的单链表是否为空
		return head.next == null;
	}
	public int lenght(){//求带头结点的单链表的长度
		Node p = head.next;//头指针
		int lenght = 0;//计数
		while(p != null){//指向后继结点
			p = p.next;
			++lenght;
		}
		
		return lenght;//返回长度
	}
	public int get(int findNum){  //读取带头结点的单链表的第I个元素
		return 0;
	}
	public void insert(int i, Object num) throws Exception {//在第i个元素前插入一个值为x的新结点
		Node p = head;//初始化p为头结点，j为计数器
		int j = -1;
		while( p != null && j < i - 1){
			p = p.next;
			++j;
		}
		if(j > i - 1 || p == null)//越界
			throw new Exception("越界的插入，失败");//抛出异常
		Node s = new Node(num);//生成新结点
		s.next = p.next;
		p.next = s;
	}
	public void remove(int i) throws Exception{  //删除结点
		Node p = head.next;
		int j = -1;
		while(p.next != null && j < i - 1){
			p = p.next;
			j++;
		}
		if(j > i - 1 || p.next == null){
			throw new Exception("删除位置不合法");
		}
		p.next = p.next.next;
	}
	public int indexOf(Object num){ //查找值为x的结点
		Node p = head.next;//初始化指针
		int j = 0;
		while(p != null && !p.data.equals(num)){
			p = p.next;
			j++;
		}
		if(p != null)//寻找成功，返回位置
			return j;
		else
			return -1;
	}
	
	public void display(){//输出链表
		Node node = head.next;//取有效的结点
		while(node != null){
			System.out.println("node.data is " + node.data);
			node = node.next;
		}
		System.out.println();
	}
}
package dataStructure;


import java.util.Scanner;


public class TestLinkList {
	@SuppressWarnings("resource")
	public static void main(String[] args){
		int n = 10;
		LinkList L = new LinkList();//创建链表
		int  i = 0;
		for(i = 0; i < n; i++)
			try {
				L.insert(i, i);
				
			} catch (Exception e) {
				e.printStackTrace();
			}
			System.out.println("请输入i的值：");
			int j = new Scanner(System.in).nextInt();
			if(0 < j && j < n)
				System.out.println("第" + j + "个元素的前驱结点是：" + L.indexOf(j - 1));
			else
				System.out.println("您所查找的结点不存在");


	}
}