diff --git a/MLP_MVS/MLP_MVS.vcxproj b/MLP_MVS/MLP_MVS.vcxproj
index 4b79bac..151acca 100644
--- a/MLP_MVS/MLP_MVS.vcxproj
+++ b/MLP_MVS/MLP_MVS.vcxproj
@@ -142,7 +142,9 @@
     </Link>
   </ItemDefinitionGroup>
   <ItemGroup>
+    <ClInclude Include="..\src\Layer.h" />
     <ClInclude Include="..\src\MLP.h" />
+    <ClInclude Include="..\src\Node.h" />
     <ClInclude Include="..\src\Sample.h" />
     <ClInclude Include="..\src\Utils.h" />
   </ItemGroup>
diff --git a/MLP_MVS/MLP_MVS.vcxproj.filters b/MLP_MVS/MLP_MVS.vcxproj.filters
index 5e3ac27..8822b46 100644
--- a/MLP_MVS/MLP_MVS.vcxproj.filters
+++ b/MLP_MVS/MLP_MVS.vcxproj.filters
@@ -24,6 +24,12 @@
     <ClInclude Include="..\src\MLP.h">
       <Filter>Header Files</Filter>
     </ClInclude>
+    <ClInclude Include="..\src\Layer.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
+    <ClInclude Include="..\src\Node.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="..\src\Main.cpp">
diff --git a/src/Layer.h b/src/Layer.h
new file mode 100644
index 0000000..4eb1b65
--- /dev/null
+++ b/src/Layer.h
@@ -0,0 +1,39 @@
+//============================================================================
+// Name : Layer.h
+// Author : David Nogueira
+//============================================================================
+#ifndef LAYER_H
+#define LAYER_H
+
+#include "Node.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <iostream>
+#include <sstream>
+#include <fstream>
+#include <vector>
+#include <algorithm>
+
+class Layer {
+public:
+  Layer() {
+    m_num_nodes = 0;
+    m_nodes.clear();
+  };
+
+
+  Layer(int num_nodes, int num_inputs_per_node) {
+    m_num_nodes = num_nodes;
+    m_nodes = std::vector<Node>(num_nodes, Node(num_inputs_per_node));
+  };
+
+  ~Layer() {
+
+  };
+protected:
+  int m_num_nodes;
+  std::vector<Node> m_nodes;
+};
+
+#endif //LAYER_H
\ No newline at end of file
diff --git a/src/MLP.cpp b/src/MLP.cpp
new file mode 100644
index 0000000..b158b40
--- /dev/null
+++ b/src/MLP.cpp
@@ -0,0 +1,14 @@
+//============================================================================
+// Name : MLP.cpp
+// Author : David Nogueira
+//============================================================================
+#include "MLP.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <iostream>
+#include <sstream>
+#include <fstream>
+#include <vector>
+#include <algorithm>
+
+
diff --git a/src/MLP.h b/src/MLP.h
new file mode 100644
index 0000000..ade9b17
--- /dev/null
+++ b/src/MLP.h
@@ -0,0 +1,75 @@
+//============================================================================
+// Name : MLP.cpp
+// Author : David Nogueira
+//============================================================================
+#ifndef MLP_H
+#define MLP_H
+
+#include "Layer.h"
+#include "Sample.h"
+#include "Utils.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <iostream>
+#include <sstream>
+#include <fstream>
+#include <vector>
+#include <algorithm>
+
+class MLP {
+public:
+  MLP(int num_inputs,
+      int num_outputs,
+      int num_hidden_layers,
+      int num_nodes_per_hidden_layer,
+      double learning_rate,
+      int max_iterations,
+      double threshold) {
+
+    m_num_inputs = num_inputs;
+    m_num_outputs = num_outputs;
+    m_num_hidden_layers = num_hidden_layers;
+    m_num_nodes_per_hidden_layer = num_nodes_per_hidden_layer;
+
+    m_learning_rate = learning_rate;
+    m_max_iterations = max_iterations;
+    m_threshold = threshold;
+  };
+
+  ~MLP() {
+    m_layers.clear();
+  };
+
+  void CreateMLP() {
+    if (m_num_hidden_layers > 0) {
+      //first layer
+      m_layers.emplace_back(Layer(m_num_nodes_per_hidden_layer, m_num_inputs));
+      //subsequent layers
+      for (int i = 0; i < m_num_hidden_layers - 1; i++) {
+        m_layers.emplace_back(Layer(m_num_nodes_per_hidden_layer,
+                                    m_num_nodes_per_hidden_layer));
+      }
+      //last layer
+      m_layers.emplace_back(Layer(m_num_outputs, m_num_nodes_per_hidden_layer));
+    } else {
+      m_layers.emplace_back(Layer(m_num_outputs, m_num_inputs));
+    }
+  }
+
+
+private:
+
+  int m_num_inputs;
+  int m_num_outputs;
+  int m_num_hidden_layers;
+  int m_num_nodes_per_hidden_layer;
+
+  double m_learning_rate;
+  int m_max_iterations;
+  double m_threshold;
+
+  std::vector<Layer> m_layers;
+};
+
+#endif //MLP_H
\ No newline at end of file
diff --git a/src/Main.cpp b/src/Main.cpp
index 05b9074..2618b38 100644
--- a/src/Main.cpp
+++ b/src/Main.cpp
@@ -2,7 +2,6 @@
 // Name : Main.cpp
 // Author : David Nogueira
 //============================================================================
-
 #include "MLP.h"
 #include <stdio.h>
 #include <stdlib.h>
@@ -101,6 +100,28 @@ void LearnNOR() {
   std::cout << std::endl;
 }
 
+void LearnXOR() {
+  std::cout << "Train XOR function with mlp." << std::endl;
+
+  std::vector<TrainingSample> training_set =
+  {
+    { { 1, 0, 0 },{ 1,0 } },
+    { { 1, 0, 1 },{ 0,1 } },
+    { { 1, 1, 0 },{ 0,1 } },
+    { { 1, 1, 1 },{ 1,0 } }
+  };
+
+  MLP my_mlp(0.1, 100, 0.5);
+  my_mlp.Train(training_set, 1, 1);
+
+  assert(my_mlp.GetOutput({ 1, 0, 0 }) == 0);
+  assert(my_mlp.GetOutput({ 1, 0, 1 }) == 1);
+  assert(my_mlp.GetOutput({ 1, 1, 0 }) == 1);
+  assert(my_mlp.GetOutput({ 1, 1, 1 }) == 0);
+  std::cout << "Trained with success." << std::endl;
+  std::cout << std::endl;
+}
+
 void LearnNOT() {
   std::cout << "Train NOT function with mlp." << std::endl;
 
@@ -124,6 +145,7 @@ int main() {
   LearnNAND();
   LearnOR();
   LearnNOR();
+  LearnXOR();
   LearnNOT();
 
   return 0;
diff --git a/src/Node.h b/src/Node.h
new file mode 100644
index 0000000..f3ea89c
--- /dev/null
+++ b/src/Node.h
@@ -0,0 +1,82 @@
+//============================================================================
+// Name : Node.h
+// Author : David Nogueira
+//============================================================================
+#ifndef NODE_H
+#define NODE_H
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <iostream>
+#include <sstream>
+#include <fstream>
+#include <vector>
+#include <algorithm>
+
+#define ZERO_WEIGHT_INITIALIZATION 1
+
+class Node {
+public:
+  Node() {
+    m_bias = 0.0;
+    //m_old_bias = 0.0;
+    m_num_inputs = 0;
+    m_weights.clear();
+    //m_old_weights.clear();
+  };
+  Node(int num_inputs) {
+    m_bias = 0.0;
+    //m_old_bias = 0.0;
+    m_num_inputs = num_inputs;
+    m_weights.clear();
+    //m_old_weights.clear();
+    m_weights = std::vector<double>(num_inputs);
+    //m_old_weights = std::vector<double>(num_inputs);
+
+    //initialize weight vector
+    std::generate_n(m_weights.begin(),
+                    num_inputs,
+                      (ZERO_WEIGHT_INITIALIZATION) ? 
+                    utils::gen_rand(0) : utils::gen_rand());
+  };
+  ~Node() {
+    m_weights.clear();
+    //m_old_weights.clear();
+  };
+  int GetInputSize() {
+    return m_num_inputs;
+  }
+  void SetInputSize(int num_inputs) {
+    m_num_inputs = num_inputs;
+  }
+  double GetBias() {
+    return m_bias;
+  }
+  //double GetOldBias() {
+  //  return m_old_bias;
+  //}
+  void SetBias(double bias) {
+    m_bias = bias;
+  }
+  //void SetOldBias(double old_bias) {
+  //  m_old_bias = old_bias;
+  //}
+  std::vector<double> & GetWeights() {
+    return m_weights;
+  }
+  //std::vector<double> & GetOldWeights() {
+  //  return m_old_weights;
+  //}
+  uint32_t GetWeightsVectorSize() const {
+    return m_weights.size();
+  }
+
+protected:
+  int m_num_inputs;
+  double m_bias;
+  //double m_old_bias;
+  std::vector<double> m_weights;
+  //std::vector<double> m_old_weights;
+};
+
+#endif //NODE_H
\ No newline at end of file
diff --git a/src/Sample.h b/src/Sample.h
index f4ca12e..c1de3bf 100644
--- a/src/Sample.h
+++ b/src/Sample.h
@@ -1,3 +1,7 @@
+//============================================================================
+// Name : Sample.h
+// Author : David Nogueira
+//============================================================================
 #ifndef TRAININGSAMPLE_H
 #define TRAININGSAMPLE_H
 
diff --git a/src/Utils.h b/src/Utils.h
index c663c41..d2af857 100644
--- a/src/Utils.h
+++ b/src/Utils.h
@@ -1,3 +1,7 @@
+//============================================================================
+// Name : Utils.h
+// Author : David Nogueira
+//============================================================================
 #ifndef UTILS_H
 #define UTILS_H
 
@@ -15,10 +19,11 @@ namespace utils {
 
 struct gen_rand {
   double factor;
+  double offset;
 public:
-  gen_rand(double r = 1.0) : factor(r / RAND_MAX) {}
+  gen_rand(double r = 2.0) : factor(r / RAND_MAX), offset(r / 2) {}
   double operator()() {
-    return rand() * factor;
+    return rand() * factor - offset;
   }
 };