diff --git a/histogram.cpp b/histogram.cpp
index ef7e79a..59ef396 100644
--- a/histogram.cpp
+++ b/histogram.cpp
@@ -2,7 +2,7 @@
 #include <vector>
 
 //Функция поиска минимума и максиммума
-static void find_minmax(const std::vector<double>& numbers, double& Min, double& Max){
+void find_minmax(const std::vector<double>& numbers, double& Min, double& Max){
     Min = numbers[0];
     Max = numbers[0];
     for (int i = 1; i < numbers.size(); i++) {
diff --git a/histogram_internal.h b/histogram_internal.h
new file mode 100644
index 0000000..160c40b
--- /dev/null
+++ b/histogram_internal.h
@@ -0,0 +1,7 @@
+#ifndef HISTOGRAM_INTERNAL_H_INCLUDED
+#define HISTOGRAM_INTERNAL_H_INCLUDED
+#include <vector>
+
+void find_minmax(const std::vector<double>& numbers, double& Min, double& Max);
+
+#endif // HISTOGRAM_INTERNAL_H_INCLUDED