diff --git a/source/main.cpp b/source/main.cpp
index 3b7d971..a4fe449 100644
--- a/source/main.cpp
+++ b/source/main.cpp
@@ -1,6 +1,7 @@
 #include <streambuf>
 #include <cstdio>
 #include <cmath>
+#include <string>
 #include <armadillo>
 #include "Rbm.hpp"
 
@@ -24,16 +25,17 @@ class RbmListener : public Rbm::IListener
 	}
 };
 
-arma::mat loadTraining(const char *pFilename)
+arma::mat loadTraining(const std::string &filename)
 {
 	uint32_t numTraining = 0;
 	uint32_t numVisible = 0;
 	FILE *pFile;
 
-	pFile = fopen(pFilename,"r");
+	pFile = fopen(filename.c_str(), "r");
 
 	if (!pFile)
 	{
+		std::cout << "Could not open " << filename << "!" << std::endl;
 		return 0;
 	}
 
@@ -67,14 +69,17 @@ arma::mat loadTraining(const char *pFilename)
 	
 }
 
-void saveWeight(const char *pFilename, size_t numVisibleX, size_t numVisibleY, const arma::mat &w, const arma::mat &bv, const arma::mat &bh)
+void saveWeight(const std::string &filename, size_t numVisibleX, size_t numVisibleY, const arma::mat &w, const arma::mat &bv, const arma::mat &bh)
 {
 	FILE *pFile;
 
-	pFile = fopen(pFilename,"w");
+	pFile = fopen(filename.c_str(), "w");
 
 	if (!pFile)
+	{
+		std::cout << "Could not open " << filename << "!" << std::endl;
 		return;
+	}
 
 	size_t numHidden = bh.n_elem;
 	size_t numVisible = bv.n_elem;
@@ -106,9 +111,10 @@ int main()
 {
 	printf("Hallo, Welt!\n");
 
+	const std::string project("mnist");
 	RbmListener statusDisplay;
 	Rbm::Params params;
-	arma::mat batch = loadTraining("mnist_2.training.dat");
+	arma::mat batch = loadTraining(project + std::string(".training.dat"));
 
 	size_t numTraining = batch.n_rows;
 	size_t numVisible = batch.n_cols;
@@ -121,7 +127,7 @@ int main()
 	arma::mat bh = arma::zeros(1, numHidden);
 	Rbm rbm(params, w, bv, bh);
 	rbm.train(batch, 1000, 100, &statusDisplay);
-	saveWeight("mnist_2.weights.dat", 28, 28, w, bv, bh);
+	saveWeight(project + std::string(".weights.dat"), 28, 28, w, bv, bh);
 	arma::mat v = arma::randu(numTraining, numVisible);
 	arma::mat h = rbm.toHiddenProbs(v);
 	arma::mat r = rbm.toVisibleProbs(h);