[C#]Stack类的实现

Stack的实现必须采用一种基本结构来保存数据。因为再新数据项进栈的时候不需要担心调整表的大小，所以选择用arrayList.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Collections;

namespace Data_structure_and_algorithm
{
    class CStack
    {
        private int p_index;
        private ArrayList list;
        public CStack() 
        {
            list = new ArrayList();
            p_index = -1;
        }
        public int count 
        {
            get { return list.Count; }
        }
        public void push(object item) 
        {
            list.Add(item);
            p_index++;
        }
        public object pop() 
        {
            object obj=list[p_index];
            list.RemoveAt(p_index);
            p_index--;
            return obj;
        }
        public void clear() 
        {
            list.Clear();
            p_index = -1;
        }
        public object peek() 
        {
            return list[p_index];
        }
    }
}

利用此类来实现判断回文数：

        public static void CStackTest() 
        {
            CStack alist = new CStack();
            string ch;
            string word = "sees";
            bool ispalindrome = true;

            for (int x = 0; x < word.Length; x++) 
            {
                alist.push(word.Substring(x,1));
            }
            int pos = 0;
            while (alist.count > 0) 
            {
                ch = alist.pop().ToString();
                if (ch != word.Substring(pos,1)) 
                {
                    ispalindrome = false;
                    break;
                }
                pos++;
            }
            if (ispalindrome)
            {
                Console.WriteLine(word + " is a palindrome");
            }
            else 
            {
                Console.WriteLine(word + " is not a palindrome");
            }
            Console.Read();
        }