组合数据的输出

    排列组合是高中是学到的 知识，理论上非常清楚。但怎样使用代码实现，却一直没有尝试过，近段时间因为项目须要，写一个组合的算法。想不到却花费了不少时间。

   需求非常easy，就是典型的组合应用。

比如输入：C0,C1,C2,C3,C4,输出C0,C1,C2,C3,C4的全部组合。

     因为输入数据的个数不确定。自然不能使用一般的循环，仅仅能使用递归加循环。

  经过不断的实验的和測试，发现有两种实现方法。

  1依据组合长度的输出，比如对于输入C0,C1,C2,C3,C4的五个元素，先输出，一个元素的全部组合，再输出两个元素的全部组合，一次类推，直到全部元素的组合都输出完毕。

 详细实现代码：

 

  public static void CreatSumData2(List<string> columnNameList)
        {
            string res = "";
            // 一个元素
            for (int i = 0; i < columnNameList.Count; i++)//
            {
                string name = columnNameList[i];
                List<string> listContion = new List<string>();
                listContion.Add(name);
                res += OutPutData(listContion);
                listContion.Clear();
            }
            //两个以上元素
            int length = 2;
            int max = columnNameList.Count;//组合的最大元素个数
            while (length <= max)//一直循环到全部元素的组合,每一次循环，处理某一个长度的组合
            {
                for (int i = 0; i <= columnNameList.Count - length + 1; i++)//
                {
                    string name = columnNameList[i];
                    int currentlLvel = i + 1;
                    List<string> hasAddNameList = new List<string>();//保存已加入的元素
                    hasAddNameList.Add(name);
                    res += addOneContion(hasAddNameList, columnNameList, currentlLvel, length);
                    hasAddNameList.Clear();//清空元素
                }
                length++;
            }
            WrieData(res);
        }
        /// <summary>
        /// 加入一个元素
        /// </summary>
        /// <param name="hasAddNameList">已加入的元素</param>
        /// <param name="columnNameList">全部可能的元素</param>
        /// <param name="currentlLvel"></param>
        /// <param name="currentMaxLength">加入的元素的最大个数</param>
        /// <returns></returns>
        private static string addOneContion(List<string> hasAddNameList, List<string> columnNameList, int currentlLvel, int currentMaxLength)
        {
            string res = "";
            bool hasAddOutNames = false;
            int currentlLvelInner = currentlLvel;
            if (hasAddNameList.Count == currentMaxLength)
            {
                res += OutPutData(hasAddNameList);
                hasAddNameList.Clear();
                return res;
            }
            List<string> hasAddNameListInner = new List<string>();
            for (int i = currentlLvelInner; i < columnNameList.Count; i++)//
            {
                string colunmname = columnNameList[i];
                currentlLvelInner++;
                if (!hasAddOutNames)
                {
                    hasAddNameListInner.AddRange(hasAddNameList);
                    hasAddOutNames = true;
                }
                hasAddNameListInner.Add(colunmname);
                if (hasAddNameListInner.Count == currentMaxLength)
                {
                    res += OutPutData(hasAddNameListInner);
                    hasAddNameListInner.Clear();
                    hasAddOutNames = false;
                }
                else
                {
                    res += addOneContion(hasAddNameListInner, columnNameList, currentlLvelInner, currentMaxLength);
                    hasAddNameListInner.Clear();
                    hasAddOutNames = false;
                }
            }
            return res;
        }     

改进版：

 public static void CreatSumData22(List<string> columnNameList)
        {
            string res = "";
            // 一个元素
            for (int i = 0; i < columnNameList.Count; i++)//
            {
                string name = columnNameList[i];
                List<string> listContion = new List<string>();             
                res += OutPutData(listContion, name);              
            }
            //两个以上元素
            int length = 2;
            int max = columnNameList.Count;//组合的最大元素个数
            while (length <= max)//一直循环到全部元素的组合,每一次循环，处理某一个长度的组合
            {
                for (int i = 0; i <= columnNameList.Count - length + 1; i++)//
                {
                    string name = columnNameList[i];                 
                    List<string> hasAddNameList = new List<string>();//保存已加入的元素             
                    res += addOneContion(hasAddNameList, columnNameList, i + 1, length, name);               
                }
                length++;
            }
            WrieData(res);
        }
        /// <summary>
        /// 加入一个元素
        /// </summary>
        /// <param name="hasAddNameList">已加入的元素</param>
        /// <param name="columnNameList">全部可能的元素</param>
        /// <param name="startIndex"></param>
        /// <param name="currentMaxLength">加入的元素的最大个数</param>
        /// <returns></returns>
        private static string addOneContion(List<string> hasAddNameList, List<string> columnNameList, int startIndex, int currentMaxLength,string parentName)
        {
            string res = ""; 
            List<string> hasAddNameListInner = new List<string>();
            hasAddNameListInner.AddRange(hasAddNameList);
            hasAddNameListInner.Add(parentName);
            for (int i = startIndex; i < columnNameList.Count; i++)//
            {
                string colunmname = columnNameList[i];
                if (hasAddNameListInner.Count + 1 == currentMaxLength)
                {        
                    res += OutPutData(hasAddNameListInner, colunmname);                  
                }
                else
                {
                    res += addOneContion(hasAddNameListInner, columnNameList, i+1, currentMaxLength, colunmname);                 
                }
            }
            return res;
        }
        private static string OutPutData(List<string> listold,string name)
        {
            List<string> listoldinner = new List<string>();
            listoldinner.AddRange(listold);
            listoldinner.Add(name);           
            return OutPutData(listoldinner);
        }

2 依据元素的输出。比如对于输入C0,C1,C2,C3,C4的五个元素。先输出包括C0这个元素的全部组合，再输出包括C1但不包括C0的全部组合。一次类推。直到全部元素的组合都输出完毕。

详细实现代码

 public static void CreatSumData(List<string> columnNameList)
        {
            string res = "";
            List<string> hasAddNameList = new List<string>();
            for (int i = 0; i < columnNameList.Count; i++)//
            {
                string colunmname = columnNameList[i];
                int currentlLvel = i;
                currentlLvel++;           
                hasAddNameList.Add(colunmname);
                res += OutPutData(hasAddNameList);
                res += CreatNextLevelData(hasAddNameList, columnNameList, currentlLvel);
                hasAddNameList.Clear();

            }
            WrieData(res);
        }
        private static string CreatNextLevelData(List<string> hasAddNameList, List<string> columnNameList, int currentlLvel)
        {
            string res = "";
            List<string> hasAddNameListInner = new List<string>();
            bool hasAddOutNames = false;
        
            int currentlLvelInner = currentlLvel;
            for (int i = currentlLvelInner; i < columnNameList.Count; i++)//
            {
                if (!hasAddOutNames) {
                    hasAddNameListInner.AddRange(hasAddNameList);
                }
                string colunmname = columnNameList[i];
                currentlLvelInner++;
                hasAddNameListInner.Add(colunmname);
                res += OutPutData(hasAddNameListInner);
                res += CreatNextLevelData(hasAddNameListInner, columnNameList, currentlLvelInner);
                hasAddOutNames = false;
                hasAddNameListInner.Clear();
            }
            return res;
        }

改进版

 public static void CreatSumData1(List<string> columnNameList)
        {
            string res = "";
            List<string> hasAddNameList = new List<string>();
            for (int i = 0; i < columnNameList.Count; i++)//
            {
                string colunmname = columnNameList[i];                        
                res += OutPutData(hasAddNameList, colunmname);
                res += CreatNextLevelData(hasAddNameList, columnNameList, i+1, colunmname);            
            }
            WrieData(res);
        }
        private static string CreatNextLevelData(List<string> hasAddNameList, List<string> columnNameList, int startIndex, string parentcolumn)
        {
            string res = "";
            List<string> hasAddNameListInner = new List<string>();
            hasAddNameListInner.AddRange(hasAddNameList);
            hasAddNameListInner.Add(parentcolumn);
            for (int i = startIndex; i < columnNameList.Count; i++)//
            {              
                string colunmname = columnNameList[i];                  
                res += OutPutData(hasAddNameListInner, colunmname);
                res += CreatNextLevelData(hasAddNameListInner, columnNameList, i + 1, colunmname);          
            }
            return res;
        }

完整的代码：

      #region 依据组合长度的输出
        public static void CreatSumData2(List<string> columnNameList)
        {
            string res = "";
            // 一个元素
            for (int i = 0; i < columnNameList.Count; i++)//
            {
                string name = columnNameList[i];
                List<string> listContion = new List<string>();
                listContion.Add(name);
                res += OutPutData(listContion);
                listContion.Clear();
            }
            //两个以上元素
            int length = 2;
            int max = columnNameList.Count;//组合的最大元素个数
            while (length <= max)//一直循环到全部元素的组合,每一次循环，处理某一个长度的组合
            {
                for (int i = 0; i <= columnNameList.Count - length + 1; i++)//
                {
                    string name = columnNameList[i];
                    int currentlLvel = i + 1;
                    List<string> hasAddNameList = new List<string>();//保存已加入的元素
                    hasAddNameList.Add(name);
                    res += addOneContion(hasAddNameList, columnNameList, currentlLvel, length);
                    hasAddNameList.Clear();//清空元素
                }
                length++;
            }
            WrieData(res);
        }
        public static void CreatSumData22(List<string> columnNameList)
        {
            string res = "";
            // 一个元素
            for (int i = 0; i < columnNameList.Count; i++)//
            {
                string name = columnNameList[i];
                List<string> listContion = new List<string>();             
                res += OutPutData(listContion, name);              
            }
            //两个以上元素
            int length = 2;
            int max = columnNameList.Count;//组合的最大元素个数
            while (length <= max)//一直循环到全部元素的组合,每一次循环，处理某一个长度的组合
            {
                for (int i = 0; i <= columnNameList.Count - length + 1; i++)//
                {
                    string name = columnNameList[i];                 
                    List<string> hasAddNameList = new List<string>();//保存已加入的元素             
                    res += addOneContion(hasAddNameList, columnNameList, i + 1, length, name);               
                }
                length++;
            }
            WrieData(res);
        }
        /// <summary>
        /// 加入一个元素
        /// </summary>
        /// <param name="hasAddNameList">已加入的元素</param>
        /// <param name="columnNameList">全部可能的元素</param>
        /// <param name="startIndex"></param>
        /// <param name="currentMaxLength">加入的元素的最大个数</param>
        /// <returns></returns>
        private static string addOneContion(List<string> hasAddNameList, List<string> columnNameList, int startIndex, int currentMaxLength,string parentName)
        {
            string res = ""; 
            List<string> hasAddNameListInner = new List<string>();
            hasAddNameListInner.AddRange(hasAddNameList);
            hasAddNameListInner.Add(parentName);
            for (int i = startIndex; i < columnNameList.Count; i++)//
            {
                string colunmname = columnNameList[i];
                if (hasAddNameListInner.Count + 1 == currentMaxLength)
                {        
                    res += OutPutData(hasAddNameListInner, colunmname);                  
                }
                else
                {
                    res += addOneContion(hasAddNameListInner, columnNameList, i+1, currentMaxLength, colunmname);                 
                }
            }
            return res;
        }
        private static string OutPutData(List<string> listold,string name)
        {
            List<string> listoldinner = new List<string>();
            listoldinner.AddRange(listold);
            listoldinner.Add(name);           
            return OutPutData(listoldinner);
        }
        /// <summary>
        /// 加入一个元素
        /// </summary>
        /// <param name="hasAddNameList">已加入的元素</param>
        /// <param name="columnNameList">全部可能的元素</param>
        /// <param name="currentlLvel"></param>
        /// <param name="currentMaxLength">加入的元素的最大个数</param>
        /// <returns></returns>
        private static string addOneContion(List<string> hasAddNameList, List<string> columnNameList, int currentlLvel, int currentMaxLength)
        {
            string res = "";
            bool hasAddOutNames = false;
            int currentlLvelInner = currentlLvel;
            if (hasAddNameList.Count == currentMaxLength)
            {
                res += OutPutData(hasAddNameList);
                hasAddNameList.Clear();
                return res;
            }
            List<string> hasAddNameListInner = new List<string>();
            for (int i = currentlLvelInner; i < columnNameList.Count; i++)//
            {
                string colunmname = columnNameList[i];
                currentlLvelInner++;
                if (!hasAddOutNames)
                {
                    hasAddNameListInner.AddRange(hasAddNameList);
                    hasAddOutNames = true;
                }
                hasAddNameListInner.Add(colunmname);
                if (hasAddNameListInner.Count == currentMaxLength)
                {
                    res += OutPutData(hasAddNameListInner);
                    hasAddNameListInner.Clear();
                    hasAddOutNames = false;
                }
                else
                {
                    res += addOneContion(hasAddNameListInner, columnNameList, currentlLvelInner, currentMaxLength);
                    hasAddNameListInner.Clear();
                    hasAddOutNames = false;
                }
            }
            return res;
        }     

        #endregion
        #region 依据列输出
        public static void CreatSumData(List<string> columnNameList)
        {
            string res = "";
            List<string> hasAddNameList = new List<string>();
            for (int i = 0; i < columnNameList.Count; i++)//
            {
                string colunmname = columnNameList[i];
                int currentlLvel = i;
                currentlLvel++;           
                hasAddNameList.Add(colunmname);
                res += OutPutData(hasAddNameList);
                res += CreatNextLevelData(hasAddNameList, columnNameList, currentlLvel);
                hasAddNameList.Clear();

            }
            WrieData(res);
        }
        public static void CreatSumData1(List<string> columnNameList)
        {
            string res = "";
            List<string> hasAddNameList = new List<string>();
            for (int i = 0; i < columnNameList.Count; i++)//
            {
                string colunmname = columnNameList[i];                        
                res += OutPutData(hasAddNameList, colunmname);
                res += CreatNextLevelData(hasAddNameList, columnNameList, i+1, colunmname);            
            }
            WrieData(res);
        }
        private static string CreatNextLevelData(List<string> hasAddNameList, List<string> columnNameList, int startIndex, string parentcolumn)
        {
            string res = "";
            List<string> hasAddNameListInner = new List<string>();
            hasAddNameListInner.AddRange(hasAddNameList);
            hasAddNameListInner.Add(parentcolumn);
            for (int i = startIndex; i < columnNameList.Count; i++)//
            {              
                string colunmname = columnNameList[i];                  
                res += OutPutData(hasAddNameListInner, colunmname);
                res += CreatNextLevelData(hasAddNameListInner, columnNameList, i + 1, colunmname);          
            }
            return res;
        }
        private static string CreatNextLevelData(List<string> hasAddNameList, List<string> columnNameList, int currentlLvel)
        {
            string res = "";
            List<string> hasAddNameListInner = new List<string>();
            bool hasAddOutNames = false;
        
            int currentlLvelInner = currentlLvel;
            for (int i = currentlLvelInner; i < columnNameList.Count; i++)//
            {
                if (!hasAddOutNames) {
                    hasAddNameListInner.AddRange(hasAddNameList);
                }
                string colunmname = columnNameList[i];
                currentlLvelInner++;
                hasAddNameListInner.Add(colunmname);
                res += OutPutData(hasAddNameListInner);
                res += CreatNextLevelData(hasAddNameListInner, columnNameList, currentlLvelInner);
                hasAddOutNames = false;
                hasAddNameListInner.Clear();
            }
            return res;
        }
        #endregion
        private static string OutPutData(List<string> listold)
        {
            string text = "";
            for (int i = 0; i < listold.Count; i++)
            {
                string item = listold[i];
                text += "["" + item + ""]";
            }
            return text + "
";
        }
        private static void WrieData(string text)
        {
            string file = "ZuheTestout.js";
            StreamWriter sr = new StreamWriter(file);
            sr.WriteLine(text);
            sr.Close();
        }