diff --git a/histogram.cpp b/histogram.cpp
new file mode 100644
index 0000000..9deefeb
--- /dev/null
+++ b/histogram.cpp
@@ -0,0 +1,59 @@
+#include "histogram.h"
+#include <iostream>
+#include <vector>
+using namespace std;
+
+static void find_minmax(const vector<double>& numbers, double& minN, double& maxN)
+{
+    minN = numbers[0];
+    maxN = numbers[0];
+
+    for (double x: numbers)
+    {
+        if (minN > x)
+        {
+            minN = x;
+        }
+        if (maxN < x)
+        {
+            maxN = x;
+        }
+    }
+}
+
+vector<size_t> make_histogram(const vector<double>& numbers, size_t bin_count)
+{
+    double minN, maxN;
+    find_minmax( numbers, minN, maxN);
+
+    vector <size_t> bins(bin_count);
+    double diff = (maxN - minN) / bin_count;
+    size_t max_count = 0;
+    for (size_t i = 0; i <numbers.size() ; i++)
+    {
+        bool found = false;
+        for (size_t j = 0; (j < bin_count - 1) && !found; j++)
+        {
+            auto lo = minN + j * diff;
+            auto hi = minN + (j + 1) * diff;
+            if ((lo <= numbers[i]) && (hi > numbers[i]))
+            {
+                bins[j]++;
+                if (bins[j] > max_count)
+                {
+                    max_count = bins[j];
+                }
+                found = true;
+            }
+        }
+        if(!found)
+        {
+            bins[bin_count - 1]++;
+            if (bins[bin_count - 1] > max_count)
+            {
+                max_count = bins[bin_count - 1];
+            }
+        }
+    }
+    return bins;
+}
diff --git a/histogram.h b/histogram.h
new file mode 100644
index 0000000..0d8dc8c
--- /dev/null
+++ b/histogram.h
@@ -0,0 +1,9 @@
+#ifndef HISTOGRAM_H_INCLUDED
+#define HISTOGRAM_H_INCLUDED
+
+#include <vector>
+
+std::vector<size_t>
+make_histogram(const std::vector<double>& numbers, size_t bin_count);
+
+#endif // HISTOGRAM_H_INCLUDED
diff --git a/main.cpp b/main.cpp
index 604f7d8..33dbb41 100644
--- a/main.cpp
+++ b/main.cpp
@@ -1,5 +1,7 @@
 #include <iostream>
 #include <vector>
+#include "histogram.h"
+#include "text.h"
 
 using namespace std;
 
@@ -28,111 +30,6 @@ input_data()
     return in;
 }
 
-void find_minmax( const vector<double>& numbers, double& minN, double& maxN)
-{
-    minN = numbers[0];
-    maxN = numbers[0];
-
-    for (double x: numbers)
-    {
-        if (minN > x)
-        {
-            minN = x;
-        }
-        if (maxN < x)
-        {
-            maxN = x;
-        }
-    }
-}
-
-vector<size_t> make_histogram(const vector<double>& numbers, size_t bin_count)
-{
-    double minN, maxN;
-    find_minmax( numbers, minN, maxN);
-
-    vector <size_t> bins(bin_count);
-    double diff = (maxN - minN) / bin_count;
-    size_t max_count = 0;
-    for (size_t i = 0; i <numbers.size() ; i++)
-    {
-        bool found = false;
-        for (size_t j = 0; (j < bin_count - 1) && !found; j++)
-        {
-            auto lo = minN + j * diff;
-            auto hi = minN + (j + 1) * diff;
-            if ((lo <= numbers[i]) && (hi > numbers[i]))
-            {
-                bins[j]++;
-                if (bins[j] > max_count)
-                {
-                    max_count = bins[j];
-                }
-                found = true;
-            }
-        }
-        if(!found)
-        {
-            bins[bin_count - 1]++;
-            if (bins[bin_count - 1] > max_count)
-            {
-                max_count = bins[bin_count - 1];
-            }
-        }
-    }
-    return bins;
-}
-
-void show_histogram_text(const vector <size_t>& bins,size_t bin_count, size_t max_count)
-{
-    const size_t SCREEN_WIDTH = 80;
-    const size_t MAX_ASTERISK = SCREEN_WIDTH - 3 - 1;
-
-    bool scaling = false;
-
-    if (max_count > MAX_ASTERISK)
-    {
-        scaling = true;
-    }
-
-    for (size_t i = 0; i < bin_count; i++)
-    {
-        if (bins[i] < 10)
-        {
-            cout << "  ";
-        }
-        else if (bins[i] < 100)
-        {
-            cout << " ";
-        }
-        else
-        {
-            cout << "";
-        }
-        cout << bins[i] << '|';
-
-        size_t number_of_stars = bins[i];
-
-        if (scaling)
-        {
-            if (bins[i] == max_count)
-            {
-                number_of_stars = MAX_ASTERISK * 1.0;
-            }
-            else
-            {
-                number_of_stars = MAX_ASTERISK * (static_cast<double>(bins[i]) / max_count);
-            }
-        }
-
-        for (size_t j = 0; j < number_of_stars; j++)
-        {
-            cout << '*';
-        }
-        cout << endl;
-    }
-}
-
 int main()
 {
     size_t max_count;
diff --git a/text.cpp b/text.cpp
new file mode 100644
index 0000000..6b55eef
--- /dev/null
+++ b/text.cpp
@@ -0,0 +1,54 @@
+#include "text.h"
+#include <iostream>
+#include <vector>
+using namespace std;
+
+void show_histogram_text(const vector <size_t>& bins,size_t bin_count, size_t max_count)
+{
+    const size_t SCREEN_WIDTH = 80;
+    const size_t MAX_ASTERISK = SCREEN_WIDTH - 3 - 1;
+
+    bool scaling = false;
+
+    if (max_count > MAX_ASTERISK)
+    {
+        scaling = true;
+    }
+
+    for (size_t i = 0; i < bin_count; i++)
+    {
+        if (bins[i] < 10)
+        {
+            cout << "  ";
+        }
+        else if (bins[i] < 100)
+        {
+            cout << " ";
+        }
+        else
+        {
+            cout << "";
+        }
+        cout << bins[i] << '|';
+
+        size_t number_of_stars = bins[i];
+
+        if (scaling)
+        {
+            if (bins[i] == max_count)
+            {
+                number_of_stars = MAX_ASTERISK * 1.0;
+            }
+            else
+            {
+                number_of_stars = MAX_ASTERISK * (static_cast<double>(bins[i]) / max_count);
+            }
+        }
+
+        for (size_t j = 0; j < number_of_stars; j++)
+        {
+            cout << '*';
+        }
+        cout << endl;
+    }
+}
diff --git a/text.h b/text.h
new file mode 100644
index 0000000..a619492
--- /dev/null
+++ b/text.h
@@ -0,0 +1,6 @@
+#ifndef TEXT_H_INCLUDED
+#define TEXT_H_INCLUDED
+#include <vector>
+void show_histogram_text(const std::vector <size_t>& bins,size_t bin_count, size_t max_count);
+
+#endif // TEXT_H_INCLUDED