void verifyChains(Chains &chains) {
cerr << "verifying chains:" << endl;
for (Chains::iterator hc = chains.begin(); hc != chains.end(); ++hc) {
if (hc->size() > 1) {
Chain::iterator j = hc->begin();
IPoint p = *j;
for (++j; j != hc->end(); ++j) {
if (!p.isNeighbour(*j)) {
cerr << "not neighbours: " << p << " <-> " << *j << endl;
}
p = *j;
}
}
}
}
