diff --git a/ch01/ex1_11.cpp b/ch01/ex1_11.cpp
index 08c3a14f..888b178e 100644
--- a/ch01/ex1_11.cpp
+++ b/ch01/ex1_11.cpp
@@ -8,7 +8,10 @@ using std::cin;
 void print_range(int lo, int hi)
 {
     if (lo > hi)
+    {
         print_range(hi, lo);
+        return;
+    }
     for (int i = lo; i != hi; ++i)
         cout << i << " ";
 }