matC=matrix_multiply(&gf, matG, matS, n, t, t, len, w,&toto);
}
auto end = std::chrono::system_clock::now();
std::chrono::duration<double> elapsed_seconds = end-start;
total_time+=elapsed_seconds.count();
matC=matrix_multiply(&gf, matG, matS, n, t, t, len, w,&toto);
}
auto end = std::chrono::system_clock::now();
std::chrono::duration<double> elapsed_seconds = end-start;
total_time+=elapsed_seconds.count();