if (vertex_in_triangles[v] != expd) {
fprintf(stderr,"vertex %02x used for %d triangles, expected %d\n",
v, vertex_in_triangles[v], expd);
if (vertex_in_triangles[v] != expd) {
fprintf(stderr,"vertex %02x used for %d triangles, expected %d\n",
v, vertex_in_triangles[v], expd);