svg: пустое изображение

main.cpp

@@ -3,6 +3,7 @@
 #include <string>
 #include "histogram.h"
 #include "text.h"
+#include "svg.h"
 using namespace std;
 struct Input {
     vector<double> numbers;
@@ -35,6 +36,6 @@ int main()
 
     auto in = input_data();
     auto bins = make_histogram(in.numbers, in.bin_count);
-    show_histogram_text(bins, MAX_ASTERISK, in.bin_count);
+    show_histogram_svg(bins);
     return 0;
 }

svg.cpp

@@ -0,0 +1,25 @@
+#include <iostream>
+#include <vector>
+using namespace std;
+
+void
+svg_begin(double width, double height) {
+    cout << "<?xml version='1.0' encoding='UTF-8'?>\n";
+    cout << "<svg ";
+    cout << "width='" << width << "' ";
+    cout << "height='" << height << "' ";
+    cout << "viewBox='0 0 " << width << " " << height << "' ";
+    cout << "xmlns='http://www.w3.org/2000/svg'>\n";
+}
+
+void
+svg_end() {
+    cout << "</svg>\n";
+}
+
+void
+show_histogram_svg(const vector <double>& bins) {
+    svg_begin(400, 300);
+    svg_end();
+}
+

svg.h

@@ -0,0 +1,4 @@
+#pragma once
+
+void
+show_histogram_svg(const std::vector<double>& bins);

text.cpp

@@ -4,7 +4,7 @@
 using namespace std;
 
 void
-show_histogram_text (const vector<double>& bins,size_t MAX_ASTERISK, size_t bin_count){
+show_histogram_text (const vector<double>& bins, size_t MAX_ASTERISK, size_t bin_count){
     double max_count = bins[0];
     for (double x: bins){
         if (x > max_count) {