集合

 //集合ArrayList:跟数组比，不限数量，不限类型
           
            ArrayList arr = new ArrayList();
            arr.Add(5);
            arr.Add(7);
            arr.Add("fadf");
            string s = "你好";
            arr.Add(s);
            Console.WriteLine(arr[0]);
         
            int count = arr.Count;
            Console.WriteLine("元素个数为：" + count);
           // arr.Clear();//清空集合
            bool isok = arr.Contains(7);//包含
            Console.WriteLine(isok);
            
           // arr.Insert(2,"zhangsan");

           // arr.Remove("zhangsan");
           // arr.RemoveAt(2);
            
           int index =  arr.IndexOf("fadf");
           Console.WriteLine("索引为："+index);
            foreach (object o in arr)
            {
                Console.WriteLine(o);
            }
          
            //输入十个人的分数，放入集合当中
            ArrayList list = new ArrayList();

            for (int i = 0; i < 5; i++)
            {
                string s = Console.ReadLine();
                list.Add(s);
            }

            list.Sort();//排序
            list.Reverse();//翻转集合

            foreach (string s in list)
            {
                Console.WriteLine(s);
            }
          

            //特殊集合stack queue hashtable
          
            //栈桥
            Stack s = new Stack();
            s.Push(3);//推入集合
            s.Push(5);
            s.Push(7);

            foreach(int a in s)
            {
                Console.WriteLine(a);
            }

            int count = s.Count;

            int qu = int.Parse(s.Pop().ToString());//弹出最后一个元素

            Console.WriteLine(qu);
            s.Clear();//清空集合
          
            //队列
            Queue q = new Queue();
            q.Enqueue(3);
            q.Enqueue(5);
            q.Enqueue(7);
           
            int chu = int.Parse(q.Dequeue().ToString());
            foreach (int a in q)
            {
                Console.WriteLine(a);
            }
        

            Hashtable hs = new Hashtable();
            hs.Add(3, "张三");
            hs.Add("4", "李四");

            //foreach (int i in hs.Keys)
            //{
            //    Console.WriteLine(i);
            //}

            foreach (string s in hs.Values)
            {
                Console.WriteLine(s);
            }

            int count = hs.Count;//元素个数

            Console.WriteLine(hs["4"]);

            Console.ReadLine();