diff --git a/math/modular_exponentiation.cpp b/math/modular_exponentiation.cpp
index b85a9c874..4ddec1b2a 100644
--- a/math/modular_exponentiation.cpp
+++ b/math/modular_exponentiation.cpp
@@ -91,5 +91,5 @@ static void test()
 int main() 
 { 
     test(); // execute the tests
-	return 0; 
+    return 0; 
 }