diff --git a/bin/Debug/devlab1.exe b/bin/Debug/devlab1.exe
index e209b2a..d1b77f8 100644
Binary files a/bin/Debug/devlab1.exe and b/bin/Debug/devlab1.exe differ
diff --git a/devlab1.cbp b/devlab1.cbp
index f398066..54beaa3 100644
--- a/devlab1.cbp
+++ b/devlab1.cbp
@@ -35,7 +35,12 @@
 		<Linker>
 			<Add option="-static-libstdc++" />
 		</Linker>
+		<Unit filename="histogram.cpp" />
+		<Unit filename="histogram.h" />
+		<Unit filename="histogram_internal.h" />
 		<Unit filename="main.cpp" />
+		<Unit filename="text.cpp" />
+		<Unit filename="text.h" />
 		<Extensions />
 	</Project>
 </CodeBlocks_project_file>
diff --git a/devlab1.depend b/devlab1.depend
index 2186c4e..3936491 100644
--- a/devlab1.depend
+++ b/devlab1.depend
@@ -1,5 +1,18 @@
 # depslib dependency file v1.0
-1676897437 source:c:\program files\codeblocks\devlab1\main.cpp
+1680528158 source:c:\program files\codeblocks\devlab1\main.cpp
 	<iostream>
 	<vector>
+	"histogram.h"
+	"text.h"
+
+1680530141 c:\program files\codeblocks\devlab1\histogram.h
+	<vector>
+
+1680530029 source:c:\program files\codeblocks\devlab1\histogram.cpp
+	"histogram.h"
+	<vector>
+
+1680530385 c:\program files\codeblocks\devlab1\text.h
+	<vector>
+	<iostream>
 
diff --git a/devlab1.layout b/devlab1.layout
index 314cf27..cecc2f7 100644
--- a/devlab1.layout
+++ b/devlab1.layout
@@ -2,9 +2,29 @@
 <CodeBlocks_layout_file>
 	<FileVersion major="1" minor="0" />
 	<ActiveTarget name="Debug" />
-	<File name="main.cpp" open="1" top="1" tabpos="1" split="0" active="1" splitpos="0" zoom_1="0" zoom_2="0">
+	<File name="histogram.h" open="1" top="0" tabpos="2" split="0" active="1" splitpos="0" zoom_1="0" zoom_2="0">
 		<Cursor>
-			<Cursor1 position="3670" topLine="115" />
+			<Cursor1 position="123" topLine="0" />
+		</Cursor>
+	</File>
+	<File name="text.h" open="1" top="0" tabpos="4" split="0" active="1" splitpos="0" zoom_1="0" zoom_2="0">
+		<Cursor>
+			<Cursor1 position="69" topLine="0" />
+		</Cursor>
+	</File>
+	<File name="text.cpp" open="1" top="0" tabpos="5" split="0" active="1" splitpos="0" zoom_1="0" zoom_2="0">
+		<Cursor>
+			<Cursor1 position="342" topLine="0" />
+		</Cursor>
+	</File>
+	<File name="histogram.cpp" open="1" top="1" tabpos="3" split="0" active="1" splitpos="0" zoom_1="0" zoom_2="0">
+		<Cursor>
+			<Cursor1 position="344" topLine="12" />
+		</Cursor>
+	</File>
+	<File name="main.cpp" open="1" top="0" tabpos="1" split="0" active="1" splitpos="0" zoom_1="1" zoom_2="0">
+		<Cursor>
+			<Cursor1 position="187" topLine="7" />
 		</Cursor>
 	</File>
 </CodeBlocks_layout_file>
diff --git a/histogram.cpp b/histogram.cpp
new file mode 100644
index 0000000..bd4803e
--- /dev/null
+++ b/histogram.cpp
@@ -0,0 +1,43 @@
+#include "histogram.h"
+#include <vector>
+using namespace std;
+void
+find_minmax(const vector<double>& numbers, double& min, double& max)
+{
+    min = numbers[0];
+    max = numbers[0];
+    for ( size_t i=0; i < numbers.size(); i++)
+    {
+        if (numbers[i] > max) max=numbers[i];
+        if (numbers[i] < min) min=numbers[i];
+    }
+};
+
+std::vector<long long unsigned int>
+make_histogram(const vector<double>& numbers,size_t bin_count)
+{
+    float lo,hi,dif;
+    double min, max;
+    find_minmax(numbers, min, max);
+    vector <size_t> bins(bin_count) ;
+    dif=(max - min)/bin_count;
+    for(int i=0; i < numbers.size(); i++)
+    {
+        bool found = false;
+        for (int j=0; (j < bin_count-1)&&!found; j++)
+        {
+            lo= min + j*dif;
+            hi= min + (j+1)*dif;
+            if ((lo <= numbers[i]) && (numbers[i] <hi ))
+            {
+                bins[j]++;
+                found = true;
+            }
+        }
+        if (!found)
+        {
+            bins[bin_count - 1]++;
+        }
+    }
+    return bins;
+}
diff --git a/histogram.h b/histogram.h
new file mode 100644
index 0000000..b158e7a
--- /dev/null
+++ b/histogram.h
@@ -0,0 +1,10 @@
+#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/histogram_internal.h b/histogram_internal.h
new file mode 100644
index 0000000..a31e616
--- /dev/null
+++ b/histogram_internal.h
@@ -0,0 +1,6 @@
+#ifndef HISTOGRAM_INTERNAL_H_INCLUDED
+#define HISTOGRAM_INTERNAL_H_INCLUDED
+
+find_minmax(const std::vector<double>& numbers, double& min, double& max)
+
+#endif // HISTOGRAM_INTERNAL_H_INCLUDED
diff --git a/main.cpp b/main.cpp
index 9ef49d5..b27901f 100644
--- a/main.cpp
+++ b/main.cpp
@@ -1,5 +1,8 @@
 #include <iostream>
 #include <vector>
+#include "histogram.h"
+#include "text.h"
+
 using namespace std;
 
 struct Input
@@ -23,61 +26,7 @@ input_data()
     return in;
 }
 
-void
-find_minmax(const vector<double>& numbers, double& min, double& max)
-{
-    min = numbers[0];
-    max = numbers[0];
-    for ( size_t i=0; i < numbers.size(); i++)
-    {
-        if (numbers[i] > max) max=numbers[i];
-        if (numbers[i] < min) min=numbers[i];
-    }
-};
 
-std::vector<long long unsigned int>
-make_histogram(const vector<double>& numbers,size_t bin_count)
-{
-    float lo,hi,dif;
-    double min, max;
-    find_minmax(numbers, min, max);
-    vector <size_t> bins(bin_count) ;
-    dif=(max - min)/bin_count;
-    for(int i=0; i < numbers.size(); i++)
-    {
-        bool found = false;
-        for (int j=0; (j < bin_count-1)&&!found; j++)
-        {
-            lo= min + j*dif;
-            hi= min + (j+1)*dif;
-            if ((lo <= numbers[i]) && (numbers[i] <hi ))
-            {
-                bins[j]++;
-                found = true;
-            }
-        }
-        if (!found)
-        {
-            bins[bin_count - 1]++;
-        }
-    }
-    return bins;
-}
-void show_histogram_text(vector <size_t> &bins)
-{
-    for (size_t i=0; i<bins.size(); i++)
-    {
-        if (bins[i]!=0)
-        {
-            cout<<bins[i]<<" | "  ;
-            for (size_t j=0; j<bins[i]; j++)
-            {
-                cout<<"*";
-            }
-            cout<<endl;
-        }
-    }
-}
 int main()
 {
     auto in = input_data();
diff --git a/obj/Debug/histogram.o b/obj/Debug/histogram.o
new file mode 100644
index 0000000..12f41f8
Binary files /dev/null and b/obj/Debug/histogram.o differ
diff --git a/obj/Debug/main.o b/obj/Debug/main.o
index 13c18a3..94b16bc 100644
Binary files a/obj/Debug/main.o and b/obj/Debug/main.o differ
diff --git a/obj/Debug/text.o b/obj/Debug/text.o
new file mode 100644
index 0000000..e219356
Binary files /dev/null and b/obj/Debug/text.o differ
diff --git a/text.c b/text.c
new file mode 100644
index 0000000..309a776
--- /dev/null
+++ b/text.c
@@ -0,0 +1,16 @@
+#include "text.h"
+void show_histogram_text(vector <size_t> &bins)
+{
+    for (size_t i=0; i<bins.size(); i++)
+    {
+        if (bins[i]!=0)
+        {
+            cout<<bins[i]<<" | "  ;
+            for (size_t j=0; j<bins[i]; j++)
+            {
+                cout<<"*";
+            }
+            cout<<endl;
+        }
+    }
+}
diff --git a/text.cpp b/text.cpp
new file mode 100644
index 0000000..a87f304
--- /dev/null
+++ b/text.cpp
@@ -0,0 +1,17 @@
+
+#include "text.h"
+void show_histogram_text(std::vector <size_t> &bins)
+{
+    for (size_t i=0; i<bins.size(); i++)
+    {
+        if (bins[i]!=0)
+        {
+            std::cout<<bins[i]<<" | "  ;
+            for (size_t j=0; j<bins[i]; j++)
+            {
+                std::cout<<"*";
+            }
+            std::cout<<std::endl;
+        }
+    }
+}
diff --git a/text.h b/text.h
new file mode 100644
index 0000000..a6f8d25
--- /dev/null
+++ b/text.h
@@ -0,0 +1,10 @@
+#ifndef TEXT_H_INCLUDED
+#define TEXT_H_INCLUDED
+
+#include <vector>
+#include <iostream>
+
+void show_histogram_text(std::vector <size_t> &bins);
+
+
+#endif // TEXT_H_INCLUDED
diff --git a/unittest.cbp b/unittest.cbp
new file mode 100644
index 0000000..6da4486
--- /dev/null
+++ b/unittest.cbp
@@ -0,0 +1,36 @@
+<?xml version="1.0" encoding="UTF-8" standalone="yes" ?>
+<CodeBlocks_project_file>
+	<FileVersion major="1" minor="6" />
+	<Project>
+		<Option title="unittest" />
+		<Option pch_mode="2" />
+		<Option compiler="gcc" />
+		<Build>
+			<Target title="Debug">
+				<Option output="bin/Debug/unittest" prefix_auto="1" extension_auto="1" />
+				<Option object_output="obj/Debug/" />
+				<Option type="1" />
+				<Option compiler="gcc" />
+				<Compiler>
+					<Add option="-g" />
+				</Compiler>
+			</Target>
+			<Target title="Release">
+				<Option output="bin/Release/unittest" prefix_auto="1" extension_auto="1" />
+				<Option object_output="obj/Release/" />
+				<Option type="1" />
+				<Option compiler="gcc" />
+				<Compiler>
+					<Add option="-O2" />
+				</Compiler>
+				<Linker>
+					<Add option="-s" />
+				</Linker>
+			</Target>
+		</Build>
+		<Compiler>
+			<Add option="-Wall" />
+		</Compiler>
+		<Extensions />
+	</Project>
+</CodeBlocks_project_file>
diff --git a/unittest.layout b/unittest.layout
new file mode 100644
index 0000000..593c06e
--- /dev/null
+++ b/unittest.layout
@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="UTF-8" standalone="yes" ?>
+<CodeBlocks_layout_file>
+	<FileVersion major="1" minor="0" />
+	<ActiveTarget name="Debug" />
+</CodeBlocks_layout_file>