#include <boost/numeric/ublas/vector.hpp>
#include <boost/numeric/ublas/matrix.hpp>
#include <boost/numeric/ublas/io.hpp>

using namespace boost::numeric::ublas;

int main() {
    vector<double> x(2);
    x(0) = 1; x(1) = 2;
    matrix<double> A(2,2);
    A(0,0) = 0; A(0,1) = 1;
    A(1,0) = 2; A(1,1) = 3;

    vector<double> y = prod(A, x);

    std::cout << "y=" << y << std::endl;
    std::cout << "A=" << A << std::endl;
    return 0;
}