class AulaDeMatriz
{
  void imprimeMatrizBidimensional(double m[][])
  {
    for(int i = 0; i < m.length; i++)
    {
      for(int j = 0; j < m[0].length; j++)
        System.out.print(m[i][j] + " ");
      System.out.println();
    }
  }
  double calculaSoma(double m[][])
  {
    double soma = 0.0;
    for(int i = 0; i < m.length; i++)
      for(int j = 0; j < m[0].length; j++)
         soma+= m[i][j];
    return soma;
  }
  double [][] calculaTransposta(double m[][])
  {
    double [][]t = new double[m[0].length][m.length];
    for(int i = 0; i < m.length; i++)
      for(int j = 0; j < m[0].length; j++)
         t[j][i] = m[i][j];
    return t;
  }
  void imprimeDiagonal(double m[][])
  {
    if (m.length == m[0].length)
    {
      for(int i = 0; i < m.length; i++)
        System.out.print(m[i][i] + " ");
      System.out.println();
    }
    else
      System.out.println("A matriz n‹o Ž quadrada");
  }
  double [][] calculaProduto( double [][]a, double [][]b)
  {
    double [][]prod = new double[a.length][b[0].length];
    for(int i = 0; i < a.length; i++)
      for(int j = 0; j < b[0].length; j++)
      {
         for(int k = 0; k < a[0].length; k++)
           prod[i][j] = prod[i][j] + a[i][k]*b[k][j];
      }
    return prod;
  }
}