diff --git a/main.cpp b/main.cpp
index 2c3aecf..94b6370 100644
--- a/main.cpp
+++ b/main.cpp
@@ -10,24 +10,24 @@ struct Input {
 };
 
 Input
-input_data(){
+input_data(istream& in){
     size_t number_count;
-    cin >> number_count;
+    in >> number_count;
 
-    Input in;
-    in.numbers.resize(number_count);
+    Input inp;
+    inp.numbers.resize(number_count);
 
     for (size_t i = 0; i < number_count; i++){
-        cin >> in.numbers[i];
+        in >> inp.numbers[i];
     }
 
-    cin >> in.bin_count;
+    in >> inp.bin_count;
 
-    return in;
+    return inp;
 }
 
 int main(){
-    auto in = input_data();
+    auto in = input_data(cin);
     auto bins = make_histogram(in.numbers, in.bin_count);
     auto borders = make_borders(in.numbers, in.bin_count);
     show_histogram_svg(bins, borders, in.bin_count);