pass 2D array in C++ functions/c++中调用函数时传递2维数组

template < int M, int N >
void printMat(int (&mat) [M][N]) {
  for (int i=0; i < M; i++)
  {
    for (int j=0; j < N; j++)
    {
      std::cout << mat[i][j] << "\t";
    }
    std::cout << std::endl;
  }
  return;
}