stacktest.java.bak

一份自己实现的一些java的数据结构

import java.util.*;

class MyStack {
	
	int keyWord;
	MyStack next;	
	
	public MyStack(int keyWord,MyStack next){
		this.keyWord = keyWord;
		this.next = next;	
	}
	
	public MyStack(int keyWord){
		this.keyWord = keyWord;
		this.next = null;	
	}
}


public class StackTest {
	MyStack sk = null;
	
	public void push(int count){
		MyStack q = sk;
		if(sk == null)
			sk = q = new MyStack(count);
		else{
			//MyStack p = new MyStack(count,q);
			//sk = p;	
			MyStack p = new MyStack(count);
			p.next = q;
			sk = p;
		}
	}
	
	public int pop(){
		int count = 0;
		if(sk != null){
			//System.out.println(sk.keyWord);
			count = sk.keyWord;
			//return sk.keyWord;
			MyStack q = sk;	
			sk = q.next;
			q.next = null;
			q = null;
		}//end if
		else{
			System.out.println("the stack is empty");	
			return -1;
		}
		//return -1;
		return count;
	}
	
	public void listElements(){
		MyStack q = sk;	
			
		while(q != null){
			System.out.println("list : "+q.keyWord);	
			q = q.next;
		}	
	}
	
	public static void main(String[] args){
		StackTest test = new StackTest();
		/*test.push(1);
		System.out.println("list now ");
		test.listElements();
		System.out.println(test.pop());
		System.out.println(test.pop());
		test.push(2);
		System.out.println("list now ");
		test.listElements();
		System.out.println(test.pop());
		
		test.push(3);
		test.push(4);
		//System.out.println(test.pop());
		//System.out.println(test.pop());
		System.out.println("list now ");
		test.listElements();
		*/
		test.push(1);
		test.push(2);
		test.push(3);
		test.push(5);
		System.out.println(test.pop());
		System.out.println(test.pop());
		//System.out.println(test.pop());
		test.listElements();
		test.push(6);
		test.push(7);
		test.listElements();
		test.pop();
		test.listElements();
	}
		
}