переписала функцию input_data() и её вызов

main.cpp

@@ -10,25 +10,25 @@ struct Input{
     size_t bin_count{};
 };
 Input
-input_data()
+input_data(istream& in)
 {
-    Input in;
+    Input inn;
     size_t number_count;
-    cin >> number_count;
+    in >> number_count;
-    in.numbers.resize(number_count);
+    inn.numbers.resize(number_count);
 
     vector<double> numbers(number_count);
     for (size_t i=0; i< number_count; i++) {
-        cin >> in.numbers[i];
+        in >> inn.numbers[i];
     }
-    cin >> in.bin_count;
+    in >> inn.bin_count;
-    return in;
+    return inn;
 }
 
 int main()
 {
     size_t max_count;
-    auto in = input_data();
+    auto inn = input_data(cin);
-    auto bins = make_histogram(in.numbers, in.bin_count);
+    auto bins = make_histogram(inn.numbers, inn.bin_count);
     show_histogram_svg(bins);
 }