diff --git a/numbers.c b/numbers.c
index e8e79b4..5211acb 100644
--- a/numbers.c
+++ b/numbers.c
@@ -26,6 +26,11 @@ unsigned int *createNumbers(unsigned int len)
 {
   unsigned int *randomNumbers = malloc(len * sizeof(int));
 
+  if (!randomNumbers)
+  {
+    return NULL;
+  }
+
   // including upper limit
   int upperLimit = len * 2;