if (nodes[ip][i] == null || nodes[ip][i].alpha == Transducer.IMPOSSIBLE_WEIGHT)
// Note that skipping here based on alpha means that beta values won't
// be correct, but since alpha is infinite anyway, it shouldn't matter.
continue;
State s = t.getState(i);
TransitionIterator iter = s.transitionIterator (input, ip, output, ip);
while (iter.hasNext()) {
State destination = iter.nextState();
if (logger.isLoggable (Level.FINE))
logger.fine ("Backward Lattice[inputPos="+ip+"][source="+s.getName()+"][dest="+destination.getName()+"]");
int j = destination.getIndex();