#include <armadillo>

arma::vec* general_algorithm(
    arma::vec* sub_diag,
    arma::vec* main_diag,
    arma::vec* sup_diag,
    arma::vec* g_vec
)
{
    int n = main_diag->n_elem;
    double d;

    for (int i = 1; i < n; i++) {
        d = (*sub_diag)(i-1) / (*main_diag)(i-1);
        (*main_diag)(i) -= d*(*sup_diag)(i-1);
        (*g_vec)(i) -= d*(*g_vec)(i-1);
    }

    (*g_vec)(n-1) /= (*main_diag)(n-1);

    for (int i = n-2; i >= 0; i--) {
        (*g_vec)(i) = ((*g_vec)(i) - (*sup_diag)(i) * (*g_vec)(i+1)) / (*main_diag)(i);
    }
    return g_vec;
}


arma::vec* special_algorithm(
    double sub_sig,
    double main_sig,
    double sup_sig,
    arma::vec* g_vec
)
{

}

arma::vec* error(
    arma::vec* v_vec,
    arma::vec* a_vec
)
{

}

double time() {

}

int main() {

}