diff --git a/Makefile b/Makefile
index 2af4a7f..13f8244 100644
--- a/Makefile
+++ b/Makefile
@@ -5,7 +5,7 @@ all : myprogram
 clean :
 	rm -f *.o myprogram
 
-myprogram : main.o
+myprogram : myclasses.o main.o
 	g++ -Wall $^ -o myprogram
 
 %.o : %.c
diff --git a/main.cpp b/main.cpp
index 46d3819..d6bfd24 100644
--- a/main.cpp
+++ b/main.cpp
@@ -1,10 +1,33 @@
 #include <iostream>
 #include <forward_list>
+//#include <cmath>
+#include "myclasses.h"
+
+#include <vector>
 
 using namespace std;
 
+
 int main(int argc, char *argv[])
 {
+    Tools::activate_randomness();
 
-return 0;
+
+    cout << "Bonjour et bienvenu" << endl;
+    vector<int> v = {1,2,3,4};
+    cout << "size = " << v.size() << endl;
+    cout << "size of bool = " << sizeof(bool) << endl;
+
+    Neuron n0(3,SIGMOID);
+
+    Neuron n1(3,RELU);n1.set_output(1.0);
+    Neuron n2(3,RELU);n2.set_output(2.0);
+    Neuron n3(3,RELU);n3.set_output(-3.0);
+    forward_list<Neuron> fl;
+    fl.push_front(n1);fl.push_front(n2);fl.push_front(n3);
+    forward_list<Neuron>::iterator it(fl.begin());
+
+    n0.activate(it);
+    cout << "is = " << n0.get_output() << endl;
+    return 0;
 }
diff --git a/myclasses.cpp b/myclasses.cpp
new file mode 100644
index 0000000..f15f17d
--- /dev/null
+++ b/myclasses.cpp
@@ -0,0 +1,68 @@
+#include <iostream>
+#include <ctime>
+#include <cmath>
+#include <forward_list>
+#include "myclasses.h"
+
+using namespace std;
+
+Neuron::Neuron(int prev_layer_size, Activ activ_function)
+{
+    for(int i(1) ; i<=prev_layer_size ; i++)
+    {
+        weights.push_front(Tools::get_random(0.0, 1.0));
+    }
+    activ = activ_function;
+    bias = 0.1;
+    output = 0.0;
+    derror = 0.0;
+}
+
+void Neuron::set_output(float value)
+{
+    output = value;
+}
+
+void Neuron::activate(forward_list<Neuron>::iterator &prev_layer_it)
+{
+    set_output(bias);
+    for(forward_list<float>::iterator it(weights.begin()) ; it!=weights.end() ; ++it)
+    {
+        output += (*it) * ((*prev_layer_it).output);
+        prev_layer_it++;
+    }
+
+    switch(activ)
+    {
+    case RELU:
+        output = (output > 0.0) ? output : 0.0;
+        break;
+
+    case SIGMOID:
+        output = 1.0 / (1.0 + exp(-output));
+        break;
+    
+    case TANH:
+        output = tanh(output);
+        break;
+    
+    default:
+        //LINEAR (output=direct weighted sum) as base behavior
+        break;
+    }
+}
+
+float Neuron::get_output()//to be deleted later
+{
+    return output;
+}
+
+void Tools::activate_randomness()
+{
+    srand(time(NULL));
+}
+
+float Tools::get_random(float mini, float maxi)
+{
+    return mini + ((float)rand()/(float)RAND_MAX) * (maxi-mini);
+}
\ No newline at end of file
diff --git a/myclasses.h b/myclasses.h
new file mode 100644
index 0000000..fb6f37f
--- /dev/null
+++ b/myclasses.h
@@ -0,0 +1,55 @@
+#ifndef MYCLASSES_H
+#define MYCLASSES_H
+
+#include <forward_list>
+#include <list>
+#include <vector>
+
+
+enum Activ
+{
+    RELU, TANH, SIGMOID, LINEAR
+};
+
+class Neuron
+{
+public:
+    Neuron(int prev_layer_size, Activ activ_function);
+    void set_output(float value);
+    float get_output();//to be deleted
+    void activate(std::forward_list<Neuron>::iterator &prev_layer_it);
+private:
+    std::forward_list<float> weights;
+    float bias;
+    float output;
+    float derror;
+    Activ activ;
+};
+
+
+class Network
+{
+public:
+    Network(int n_neurons);
+    Network(const std::vector<int> &n_neurons, Activ h_activ=RELU, Activ o_activ=SIGMOID);
+    bool forward(const std::vector<float> &input, const std::vector<float> &target);
+    bool backward();
+private:
+    std::list<std::forward_list<Neuron>> layers;
+    Activ h_activ;
+    Activ o_activ;
+
+    bool _set_errors();
+};
+
+
+class Tools
+{
+public:
+    static void activate_randomness();
+    static float get_random(float mini, float maxi);
+
+private:
+};
+
+#endif
\ No newline at end of file