return ii;
}
std::cerr << "CRITICAL ERROR IN whichVertex(" << vertex_index << ") called on edge [" <<
std::cerr << "CRITICAL ERROR IN whichVertex(" << vertex_index << ") called on edge [";
std::cerr << vertex_indices_[ 0 ] << ", " << vertex_indices_[ 1 ] << "]" << std::endl;
assert(false);
exit(1);