docs: add some comments

src/petri_net_sog.cpp

@@ -512,6 +512,7 @@ Path PetriNetSOG::AbstractPath(Path path, const SOG &sog) const {
 int PetriNetSOG::ComputeWeightOfAggregate(const Aggregate *aggr,
                                           const int t_source,
                                           const int t_target) const {
+  // TODO: I think I'm  missing something here
   const bdd source = relation[t_source][aggr->state];
 
   // backtracking from t_target until t_source
@@ -519,7 +520,7 @@ int PetriNetSOG::ComputeWeightOfAggregate(const Aggregate *aggr,
   bdd current_state = SearchExitPoints(aggr->state, t_target);
   while ((source & current_state) == bdd_false()) {
     pair<int, bdd> step = StepBackward(current_state, aggr);
-    current_state = step.second & aggr->state;  // keep in the aggregate
+    current_state = step.second & aggr->state;  // stay in the aggregate
     counter++;
   }