class Solution {

 public:

     vector<int> printMatrix(vector<vector<int> > matrix) {

         int Lx = , Ly = , Rx = matrix.size() - , Ry = matrix[].size() - ;

         vector<int>res;

         while (Lx <= Rx && Ly <= Ry)

         {

             if (Lx == Rx)//只有一行

                 for (int i = Ly; i <= Ry; ++i)

                     res.push_back(matrix[Lx][i]);

             else if(Ly==Ry)//只有一列

                 for (int i = Lx; i <= Rx; ++i)

                     res.push_back(matrix[i][Ly]);

             else

             {

                 for (int i = Ly; i < Ry; ++i)

                     res.push_back(matrix[Lx][i]);

                 for (int i = Lx; i < Rx; ++i)

                     res.push_back(matrix[i][Ry]);

                 for (int i = Ry; i > Ly; --i)

                     res.push_back(matrix[Rx][i]);

                 for (int i = Rx; i > Lx; --i)

                     res.push_back(matrix[i][Ly]);

             }

             ++Lx, ++Ly;

             --Rx, --Ry;

         }

         return res;

     }

 };