// 假定矩阵元素为T

T get_col_sum(T** mat, int a_col)

{

    T sum = (T)0;

    for (int i = 0; i < M; ++i)

        sum += mat[i][a_col];

    return sum;

}

T get_row_sum(T** mat, int a_row)

{

    T sum = (T)0;

    for (int i = 0; i < N; ++i)

        sum += mat[a_row][i];

    return sum;

}

int main(int argc, char *argv[])

{

    for (int i = 0; i < M; ++i)

    {

        std::cout << "sum of row " << i << " is " << get_row_sum(mat, i) << std::endl;

    }

    for (int j = 0; j < N; ++j)

    {

        std::cout << "sum of col " << i << " is " << get_col_sum(mat, j) << std::endl;        

    }

    return 0;

}