diff --git a/cs-lab34.cbp b/cs-lab34.cbp
index 00fdc54..d794df6 100644
--- a/cs-lab34.cbp
+++ b/cs-lab34.cbp
@@ -36,7 +36,18 @@
 		<Unit filename="histogram.h">
 			<Option target="&lt;{~None~}&gt;" />
 		</Unit>
+		<Unit filename="histogram_internal.h">
+			<Option target="&lt;{~None~}&gt;" />
+		</Unit>
 		<Unit filename="main.cpp" />
+		<Unit filename="svg.cpp" />
+		<Unit filename="svg.h">
+			<Option target="&lt;{~None~}&gt;" />
+		</Unit>
+		<Unit filename="text.cpp" />
+		<Unit filename="text.h">
+			<Option target="&lt;{~None~}&gt;" />
+		</Unit>
 		<Extensions>
 			<lib_finder disable_auto="1" />
 		</Extensions>
diff --git a/svg.cpp b/svg.cpp
index f0b699d..1b344d8 100644
--- a/svg.cpp
+++ b/svg.cpp
@@ -4,27 +4,31 @@
 #include "svg.h"
 using namespace std;
 
-const auto IMAGE_WIDTH = 400;
 const auto IMAGE_HEIGHT = 300;
 const auto TEXT_LEFT = 20;
 const auto TEXT_BASELINE = 20;
 const auto TEXT_WIDTH = 50;
 const auto BIN_HEIGHT = 30;
 const auto BLOCK_WIDTH = 10;
-const auto MAX_WIDTH = IMAGE_WIDTH - TEXT_WIDTH;
 
-void
-svg_text(double left, double baseline, string text) {
-    cout << "<text x='" << left << "' y='" << baseline << "'>" << text << "</text>";
-}
-
-void
-svg_rect(double x, double y, double width, double height, string stroke = "black", string fill = "aaaaaa") {
-    cout << "<rect x='" << x<< "' y='" << y<< "' width='" << width<< "' height='" << height<< "' stroke='" << stroke<< "' fill='" << fill << "' />\n";
+double ask_width(size_t numbers_count) {
+    while (true) {
+        double width;
+        cout << "Enter width ";
+        cin >> width;
+        if (width < 70) {
+            cout << "Try again. It's too low.\n";
+        } else if (width > 800) {
+            cout << "Try again. It's too high.\n";
+        } else if (width < numbers_count * BLOCK_WIDTH / 3) {
+            cout << "Try again.\n";
+        } else {
+            return width;
+        }
+    }
 }
 
-void
-svg_begin(double width, double height) {
+void svg_begin(double width, double height) {
     cout << "<?xml version='1.0' encoding='UTF-8'?>\n";
     cout << "<svg ";
     cout << "width='" << width << "' ";
@@ -33,18 +37,25 @@ svg_begin(double width, double height) {
     cout << "xmlns='http://www.w3.org/2000/svg'>\n";
 }
 
-void
-svg_end() {
+void svg_end() {
     cout << "</svg>\n";
 }
 
-void
-show_histogram_svg(const vector<size_t>& bins) {
+void svg_text(double left, double baseline, string text) {
+    cout << "<text x='" << left << "' y='" << baseline << "'>" << text << "</text>\n";
+}
+
+void svg_rect(double x, double y, double width, double height, string stroke = "black", string fill = "aaaaaa") {
+    cout << "<rect x='" << x << "' y='" << y << "' width='" << width << "' height='" << height << "' stroke='" << stroke << "' fill='" << fill << "' />\n";
+}
+
+void show_histogram_svg(const vector<size_t>& bins) {
+    const auto IMAGE_WIDTH = ask_width(bins.size());
     const auto MAX_WIDTH = IMAGE_WIDTH - TEXT_WIDTH;
     size_t max_count = 0;
-    for (size_t x : bins) {
-        if (x > max_count) {
-            max_count = x;
+    for (size_t count : bins) {
+        if (count > max_count) {
+            max_count = count;
         }
     }
     if (max_count == 0) {
@@ -54,7 +65,8 @@ show_histogram_svg(const vector<size_t>& bins) {
     if (scale_factor > 1) {
         scale_factor = 1;
     }
-    svg_begin(400, 300);
+
+    svg_begin(IMAGE_WIDTH, IMAGE_HEIGHT);
     double top = 0;
     for (size_t bin : bins) {
         double bin_width = BLOCK_WIDTH * bin * scale_factor;
@@ -64,4 +76,3 @@ show_histogram_svg(const vector<size_t>& bins) {
     }
     svg_end();
 }
-
diff --git a/unittest.cbp b/unittest.cbp
index 7f9621b..bffa065 100644
--- a/unittest.cbp
+++ b/unittest.cbp
@@ -31,6 +31,12 @@
 		<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" />
 		<Extensions>
 			<lib_finder disable_auto="1" />
 		</Extensions>