Leetcode 之Anagrams（35）

vector<string> anagrams(vector<string> &strs)
      {
          unordered_map<string, vector<string>> group;
          for (const auto &s : strs)
          {
              string key = s;
              sort(key.begin(), key.end());
              group[key].push_back(s);
          }

          vector<string>result;
          for (auto it = group.cbegin(); it != group.cend(); it++)
          {
              //insert,在result.end()之前插入元素，返回指向元素的迭代器
              if (it->second.size() > 1)
                  result.insert(result.end(), it->second.begin(), it->second.end());
          }

          return result;
      }