#include <Eigen/Dense>
#include <iostream>

using namespace Eigen;
using namespace std;

int main() {
  ArrayXXf a(3, 3);
  ArrayXXf b(3, 3);
  a << 1, 2, 3, 4, 5, 6, 7, 8, 9;
  b << 1, 2, 3, 1, 2, 3, 1, 2, 3;

  // Adding two arrays
  cout << "a + b = " << endl << a + b << endl << endl;

  // Subtracting a scalar from an array
  cout << "a - 2 = " << endl << a - 2 << endl;
}