- refactored

- constify

source/AStack.hpp

@@ -53,7 +53,7 @@ public:
 	
 	StackType type();
 	void setName(const std::string &name);
-	size_t numLayers();
+	size_t numLayers() const;
 	virtual size_t numContext()
 	{
 		return 0;
@@ -62,6 +62,8 @@ public:
 	void delLayer(Layer *pLayer);
 	
 	Layer* getLayer(size_t layerId) const;
+	Layer* getFirstLayer() const;
+	Layer* getLastLayer() const;
 
 	bool save(const std::string &dir);
 
@@ -85,6 +87,8 @@ protected:
 
 private:
 	arma::mat m_trainingBatch;
+	size_t m_numLayers;
+	void updateNumLayers();
 	
 };