_c[0] }); return new string[] {word，s }; } Liststring _result = new Liststring(); string[] _subsetPermutations = FindPermutations(word.Substring(1)); char _firstChar = word[0]; foreach (string s in _subsetPermutations) { string _temp = _firstChar.ToString() + s; _result.Add(_temp); char[] _chars = _temp.ToCharArray(); for (int i = 0; i _temp.Length - 1; i++) {char t = _chars[i];_chars[i] = _chars[i + 1];_chars[i + 1] = t;string s2 = new string(_chars);_result.Add(s2); } } return _result.ToArray();} ， // 1. remove first char // 2. find permutations of the rest of chars// 3. Attach the first char to each of those permutations.// 3.1 for each permutation。

move firstChar in all indexes // to produce even more permutations.// 4. Return list of possible permutations.public string[] FindPermutations(string word){ if (word.Length == 2) { char[] _c = word.ToCharArray(); string s = new string(new char[] { _c[1]，。