diff --git a/cs-lab34.cbp b/cs-lab34.cbp
index d794df6..981bf7b 100644
--- a/cs-lab34.cbp
+++ b/cs-lab34.cbp
@@ -32,6 +32,7 @@
 			<Add option="-Wall" />
 			<Add option="-fexceptions" />
 		</Compiler>
+		<Unit filename="doctest.h" />
 		<Unit filename="histogram.cpp" />
 		<Unit filename="histogram.h">
 			<Option target="&lt;{~None~}&gt;" />
@@ -44,6 +45,9 @@
 		<Unit filename="svg.h">
 			<Option target="&lt;{~None~}&gt;" />
 		</Unit>
+		<Unit filename="svgg.h">
+			<Option target="&lt;{~None~}&gt;" />
+		</Unit>
 		<Unit filename="text.cpp" />
 		<Unit filename="text.h">
 			<Option target="&lt;{~None~}&gt;" />
diff --git a/svg.cpp b/svg.cpp
index 1b344d8..fafe0f0 100644
--- a/svg.cpp
+++ b/svg.cpp
@@ -11,11 +11,11 @@ const auto TEXT_WIDTH = 50;
 const auto BIN_HEIGHT = 30;
 const auto BLOCK_WIDTH = 10;
 
-double ask_width(size_t numbers_count) {
+double ask_width(size_t numbers_count, std::istream& input) {
     while (true) {
         double width;
-        cout << "Enter width ";
-        cin >> width;
+        cerr << "Write width ";
+        input >> width;
         if (width < 70) {
             cout << "Try again. It's too low.\n";
         } else if (width > 800) {
@@ -50,7 +50,7 @@ void svg_rect(double x, double y, double width, double height, string stroke = "
 }
 
 void show_histogram_svg(const vector<size_t>& bins) {
-    const auto IMAGE_WIDTH = ask_width(bins.size());
+    const auto IMAGE_WIDTH = ask_width(bins.size(), cin);
     const auto MAX_WIDTH = IMAGE_WIDTH - TEXT_WIDTH;
     size_t max_count = 0;
     for (size_t count : bins) {
diff --git a/svgg.h b/svgg.h
new file mode 100644
index 0000000..8a217ed
--- /dev/null
+++ b/svgg.h
@@ -0,0 +1,7 @@
+#ifndef SVGG_H_INCLUDED
+#define SVGG_H_INCLUDED
+
+double ask_width(size_t numbers_count);
+
+
+#endif // SVGG_H_INCLUDED
diff --git a/unittest.cbp b/unittest.cbp
index bffa065..534f497 100644
--- a/unittest.cbp
+++ b/unittest.cbp
@@ -31,9 +31,6 @@
 		<Compiler>
 			<Add option="-Wall" />
 		</Compiler>
-		<Unit filename="doctest.h">
-			<Option target="&lt;{~None~}&gt;" />
-		</Unit>
 		<Unit filename="histogram.cpp" />
 		<Unit filename="histogram_internal.h" />
 		<Unit filename="unittest.cpp" />
diff --git a/unittest2.cbp b/unittest2.cbp
new file mode 100644
index 0000000..eb0c911
--- /dev/null
+++ b/unittest2.cbp
@@ -0,0 +1,42 @@
+<?xml version="1.0" encoding="UTF-8" standalone="yes" ?>
+<CodeBlocks_project_file>
+	<FileVersion major="1" minor="6" />
+	<Project>
+		<Option title="unittest2" />
+		<Option pch_mode="2" />
+		<Option compiler="gcc" />
+		<Build>
+			<Target title="Debug">
+				<Option output="bin/Debug/unittest2" 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/unittest2" 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>
+		<Unit filename="svg.cpp" />
+		<Unit filename="svg.h" />
+		<Unit filename="svgg.h" />
+		<Unit filename="unittest2.cpp" />
+		<Extensions>
+			<lib_finder disable_auto="1" />
+		</Extensions>
+	</Project>
+</CodeBlocks_project_file>
diff --git a/unittest2.cpp b/unittest2.cpp
new file mode 100644
index 0000000..9c705f7
--- /dev/null
+++ b/unittest2.cpp
@@ -0,0 +1,10 @@
+#define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
+#include "doctest.h"
+#include <iostream>
+
+double ask_width(size_t numbers_count, std::istream& in);
+
+TEST_CASE("ask_width returns correct width") {
+    std::istringstream test_input("800\n");
+    CHECK(ask_width(10, test_input) == 800);
+}