数据结构和算法 – 10.集合

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

namespace 数据结构和算法
{
    public partial class CSet
    {

        static void Main()
        {

        }
    }

    public partial class CSet
    {
        private Hashtable data;
        public CSet()
        {
            data = new Hashtable();
        }
        // More code to follow

        public void Add(Object item)
        {
            if (!data.ContainsValue(item))
            {
                data.Add(Hash(item), item);
            }
        }

        public string Hash(object item)
        {
            char[] chars;
            string s = item.ToString();
            int hashValue = 0;
            chars = s.ToCharArray();
            for (int i = 0; i < chars.GetUpperBound(0); i++)
            {
                hashValue += (int)chars[i];
            }
            return hashValue.ToString();
        }

        public void Remove(object item)
        {
            data.Remove(Hash(item));
        }

        public int Size()
        {
            return data.Count;
        }

        //合并
        public CSet Union(CSet aSet)
        {
            CSet tempSet = new CSet();
            foreach (var hashObject in data.Keys)
            {
                tempSet.Add(this.data[hashObject]);
            }
            foreach (var hashObject in aSet.data.Keys)
            {
                if (!data.ContainsKey(hashObject))
                {
                    tempSet.Add(aSet.data[hashObject]);
                }
            }
            return tempSet;
        }

        //
        public CSet Intersection(CSet aSet)
        {
            CSet tempSet = new CSet();
            foreach (var hashObject in data.Keys)
            {
                if (aSet.data.Contains(hashObject))
                {
                    tempSet.Add(aSet.data[hashObject]);

                }
            }
            return tempSet;
        }

        public bool Subset(CSet aSet)
        {
            if (this.Size() > aSet.Size())
                return false;
            else
                foreach (Object key in this.data.Keys)
                    if (!(aSet.data.Contains(key)))
                        return false;
            return true;
        }

        public CSet Difference(CSet aSet)
        {
            CSet tempSet = new CSet();
            foreach (Object hashObject in data.Keys)
                if (!(aSet.data.Contains(hashObject)))
                    tempSet.Add(data[hashObject]);
            return tempSet;
        }
        public override string ToString()
        {
            string s = "";
            foreach (Object key in data.Keys)
                s += data[key] + " ";
            return s;
        }
    }
}