13 вариант обьединенный

main.cpp

@@ -35,7 +35,7 @@ size_t write_data(void* items, size_t item_size, size_t item_count, void* ctx) {
     return data_size;
 }
 
-void download(const string& address, Input& input) {
+Input download(const string& address) {
     stringstream buffer;
     CURL* curl = curl_easy_init();
     if (curl) {
@@ -44,14 +44,12 @@ void download(const string& address, Input& input) {
         curl_easy_setopt(curl, CURLOPT_WRITEDATA, &buffer);
         CURLcode res = curl_easy_perform(curl);
         if (res != CURLE_OK) {
-            cerr << "Error: " << curl_easy_strerror(res) << endl;
+            cerr << curl_easy_strerror(res);
             exit(1);
         }
         curl_easy_cleanup(curl);
     }
-    Input loaded = input_data(buffer, false);
-    input.numbers = loaded.numbers;
-    input.bin_count = loaded.bin_count;
+    return input_data(buffer, false);
 }
 
 void parse_args(int argc, char* argv[], Input& input, string& url) {
@@ -81,7 +79,9 @@ int main(int argc, char* argv[]) {
     if (argc > 1) {
         parse_args(argc, argv, input, url);
         if (!url.empty()) {
-            download(url, input);
+            Input downloaded = download(url);
+            input.numbers = downloaded.numbers;
+            input.bin_count = downloaded.bin_count;
         } else {
             input = input_data(cin, true);
         }