如何将几个数字进行搭配相加，得出全排列组合。

Question

比如我这里有4个数字：2、3、4、6我需要用随便几个数字搭配相加得出结果为全排列若干组合，请问如何写这样的代码？2+3=5
2+4=6
2+6=12
2+3+4=9
2+3+4+6=15
2+3+6=11
2+4+6=123+4=7
3+6=9
3+4+6=134+6=10 

Answer 1

自己稍微做下修改      string[] Sample = new string[] { "2", "3", "4", "6"};
            List<string> SampleList = new List<string>();
            SampleList.AddRange(Sample);
            
            List<string> result = getCombination(SampleList, 2);private  List<string> getCombination(List<string> SampleList, int m)
        {
            if (m == 1)
            {
                return SampleList;
            }
            List<string> result = new List<string>();
            if (SampleList.Count == m)
            {
                StringBuilder temp_sb = new StringBuilder();
                foreach (string s in SampleList)
                {
                    temp_sb.Append(s);
                }
                result.Add(temp_sb.ToString());
                Console.WriteLine(temp_sb.ToString());
                return result;
            }
            string temp_firstelement = SampleList[0];
            SampleList.RemoveAt(0);
            List<string> temp_samplist1 = new List<string>();
            temp_samplist1.AddRange(SampleList);
            List<string> temp_list1 = getCombination(temp_samplist1, m - 1);
            foreach (string s in temp_list1)
            {
                result.Add(temp_firstelement + s);
                Console.WriteLine(temp_firstelement + s);
            }
            List<string> temp_samplist2 = new List<string>();
            temp_samplist2.AddRange(SampleList);
            List<string> temp_list2 = getCombination(temp_samplist2, m);
            result.AddRange(temp_list2);
            return result;
        }

Answer 2

可以引入排列组合类http://kb.cnblogs.com/a/1652161/然后调用代码int[] arr = new int[] { 2, 3, 4, 6 };
            for (int i = 2; i <= arr.Length; i++)
            {
                List<int[]> lst_Combination = Algorithms.PermutationAndCombination<int>.GetCombination(arr, i);
                StringBuilder sb = new StringBuilder();
                for (int k = 0; k < lst_Combination.Count; k++)
                {
                    for (int j = 0; j < i; j++)
                    {
                        sb.Append(lst_Combination[k][j]);
                        if (j != i - 1)
                            sb.Append("+");
                        else
                            sb.Append("=");
                    }
                    sb.Append(lst_Combination[k].Sum());
                    sb.Append("\n");
                }
                Console.Write(sb.ToString());
            }

Answer 3

            List<int> list = new List<int> { 2, 3, 4, 6 };
            List<List<int>> nlist = new List<List<int>>();
            for (int i = 0; i < list.Count; i++)
            {
                if (nlist.Count == 0)
                {
                    nlist.Add(new List<int>());
                    nlist.Add(new List<int> { list[i] });
                    continue;
                }
                int count = nlist.Count;
                for (int j = 0; j < count; j++)
                {
                    List<int> xlist = nlist[j].ToList();
                    nlist[j].Add(list[i]);
                    nlist.Add(xlist);
                }
            }
            List<List<int>> m = nlist.Where(p => p.Count > 1).ToList();

Answer 4

测试输出            for (int i = 0; i < m.Count; i++)
            {
                for (int j = 0; j < m[i].Count; j++)
                {
                    if (j == m[i].Count - 1)
                        Console.Write("{0} = ", m[i][j]);
                    else
                        Console.Write("{0} + ", m[i][j]);
                }
                Console.Write(m[i].Sum());
                Console.WriteLine();
            }
            Console.ReadLine();

Answer 5

happy09li：
 我要的是数值相加的组合，而不是把它当成字符串的组合。
Return_false:
错误“System.Array”并不包含“Sum”的定义lizhibin11：
感觉不是c#代码啊，在我这都编译通不过。

Answer 6

这个能不能编译?        static void Main(string[] args)
        {
            List<int> list = new List<int> { 2, 3, 4, 6 };
            List<List<int>> nlist = new List<List<int>>();
            for (int i = 0; i < list.Count; i++)
            {
                if (nlist.Count == 0)
                {
                    nlist.Add(new List<int>());
                    nlist.Add(new List<int> { list[i] });
                    continue;
                }
                int count = nlist.Count;
                for (int j = 0; j < count; j++)
                {
                    List<int> xlist = new List<int>();
                    xlist.AddRange(nlist[j]);
                    nlist[j].Add(list[i]);
                    nlist.Add(xlist);
                }
            }
            for (int i = 0; i < nlist.Count; i++)
            {
                if (nlist[i].Count > 1)
                    continue;
                nlist.RemoveAt(i);
                i--;
            }            //测试输出
            for (int i = 0; i < nlist.Count; i++)
            {
                int m = 0;
                for (int j = 0; j < nlist[i].Count; j++)
                {
                    if (j == nlist[i].Count - 1)
                        Console.Write("{0} = ", nlist[i][j]);
                    else
                        Console.Write("{0} + ", nlist[i][j]);
                    m += nlist[i][j];
                }
                Console.Write(m);
                Console.WriteLine();
            }
            Console.ReadLine();
        }

Answer 7

 List<int> list = new List<int> { 2, 3, 4, 6 };
            List<List<int>> nlist = new List<List<int>>();
            for (int i = 0; i < list.Count; i++)
            {
                if (nlist.Count == 0)
                {
                    nlist.Add(new List<int>());
                    nlist.Add(new List<int> { list[i] });
                    continue;
                }
                int count = nlist.Count;
                for (int j = 0; j < count; j++)
                {
                    List<int> xlist = nlist[j].ToList();
                    nlist[j].Add(list[i]);
                    nlist.Add(xlist);
                }
            }
            List<List<int>> m = nlist.Where(p => p.Count > 1).ToList();

Answer 8

 List<int> list = new List<int> { 2, 3, 4, 6 };
            List<List<int>> nlist = new List<List<int>>();
            for (int i = 0; i < list.Count; i++)
            {
                if (nlist.Count == 0)
                {
                    nlist.Add(new List<int>());
                    nlist.Add(new List<int> { list[i] });
                    continue;
                }
                int count = nlist.Count;
                for (int j = 0; j < count; j++)
                {
                    List<int> xlist = nlist[j].ToList();
                    nlist[j].Add(list[i]);
                    nlist.Add(xlist);
                }
            }
            List<List<int>> m = nlist.Where(p => p.Count > 1).ToList();