theEdges.splice(theEdges.end(), theEdges,
theEdges.begin(), ++theEdges.begin());
TopExp::Vertices( theEdges.front(), vv[0], vv[1], true );
theEdges.splice(theEdges.end(), theEdges,
theEdges.begin(), ++theEdges.begin());
TopExp::Vertices( theEdges.front(), vv[0], vv[1], true );