diff --git a/project/histogram.cpp b/project/histogram.cpp
index 8913643..c4ed2b9 100644
--- a/project/histogram.cpp
+++ b/project/histogram.cpp
@@ -4,7 +4,7 @@
 using namespace std;
 
 
-void find_minmax(vector<double> numbers, double& min, double& max)
+static void find_minmax(vector<double> numbers, double& min, double& max)
 {
     min = numbers[0];
     max = numbers[0];