stack2.java

和树类似

package ds_java;
import ds_java.OnelinkNode;
import ds_java.Onelink1;
public class Stack2 extends Onelink1
{
	private OnelinkNode top;
	public Stack2()
	{
		top=null;
	}
	public boolean isEmpty()
	{
		return top==null;
	}
	public boolean push(int k)
	{
		OnelinkNode q=new OnelinkNode(k);
		q.next=top;
		top=q;
		return true;
	}
	public int pop()
	{
		int k=-1;
		if(!isEmpty())
		{
			k=top.data;
			top=top.next;
		}
		return k;
	}
	public int get()
	{
		if(!isEmpty())
			return top.data;
			else
			return -1;
	}
}