use bitsets

src/Core/Bag.cpp

@@ -35,7 +35,7 @@ Bag::Bag(const std::shared_ptr<PiecesList>& piecesList) :
         }
 
         for (const auto& piece : this->selectedPieces) {
-            int pieceSize = this->piecesList->lookAtPiece(piece).getPositions().size();
+            int pieceSize = this->piecesList->lookAtPiece(piece).getPositions().getSize();
             this->currentBags.at(pieceSize).push_back(piece);
         }
     }