refactoring input_data

main_original.cpp

@@ -12,20 +12,20 @@ struct Input {
     size_t bin_count{};
 };
 
-Input input_data() {
+Input input_data(istream& stream) {
     Input in;
     size_t number_count;
-    cin >> number_count;
+    stream >> number_count;
     in.numbers.resize(number_count);
     for (size_t i = 0; i < number_count; i++) {
-        cin >> in.numbers[i];
+        stream >> in.numbers[i];
     }
-    cin >> in.bin_count;
+    stream >> in.bin_count;
     return in;
 }
 
 int main() {
-    Input in = input_data();
+    Input in = input_data(cin);
     auto bins = make_histogram(in.numbers, in.bin_count);
     show_histogram_svg(bins);
     return 0;