技術標籤：資料結構java資料結構棧

陣列實現

package com.stack;

public class Stack_array {
	private int[] s;//棧陣列
	private int len;
	
	public Stack_array()
	{
		s = new int[10];//初始化大小 10
	}
	
	public Stack_array(int num)
	{
		s = new int[num];//初始化大小 num
	}
	
	/*
	 * 壓入棧
	 */
	public void push(int val){
		if(len >= s.length)
 
//棧滿
		{
			//擴充套件棧空間
			int[] ns = s.clone();
			s = new int[ns.length+10];//一次拓展10個
			for(int i = 0;i<ns.length;i++)
			{
				s[i] = ns[i];
			}
			
			s[len++] = val;//新值入棧
		}else
		{
			s[len++] = val;
		}
	}
	
	/*
	 *彈出棧頂元素 
	 */
    public int pop(){
    	if(len != 0)
    		return s[--len];
    	else
    	{
 

    		System.out.print("棧空");
    		return 0;
    	}
    }
    
    /*
     * 檢視棧頂元素
     */
    public int peak(){
    	if(len != 0)
    		return s[len-1];
    	else
    	{
    		System.out.print("棧空");
    		return 0;
    	}
    }
    
    /*
     * 檢視棧長度
     */
    public int size(
 
){
    	return len;
    }
    
    /*
     * 判斷棧是否為空
     */
    public boolean isEmpty()
    {
    	return len==0;
    }
}

鏈式實現

package com.stack;

public class Stack_link {
	 class Node {
	        public int val;
	        public Node next;
	        public Node(int val)
	        {
	            this.val = val;
	        }
	        
	        public Node()
	        {
	        	
	        }
	    }
	    
	 	private Node top;
	 	private int len;
	 	
	 	public Stack_link()
	 	{
	 		
	 	}
	 	
	 	/*
	 	 * 壓入棧
	 	 */
	    public void push(int val){
	    	Node node = new Node(val);
	    	node.next = top;
	    	top = node;
	    	len++;
	    }
	    
	    /*
	     * 彈出棧頂元素
	     */
	    public int pop(){
	    	if(top == null)
	    	{
	    		System.out.print("棧空");
	    		return 0;
	    	}else
	    	{
	    		int val = top.val;
	    		top = top.next;
	    		len--;
	    		return val;
	    	}
	    }
	    
	    /*
	     * 檢視棧頂元素
	     */
	    public int peak(){
	    	if(top==null)
	    	{
	    		System.out.print("棧空");
	    		return 0;
	    	}else
	    	{
	    		return top.val;
	    	}
	    }
	    
	    /*
	     *檢視棧長度 
	     */
	    public int size(){
	    	return len;
	    }
	    
	    /*
	     * 判斷棧是否為空
	     */
	    public boolean isEmpty()
	    {
	    	return len == 0;
	    }
}