1 files changed, 4 insertions, 3 deletions

diff --git a/Help/guide/tutorial/Step7/tutorial.cxx b/Help/guide/tutorial/Step7/tutorial.cxx
index 8156a9c..b3c6a4f 100644
--- a/Help/guide/tutorial/Step7/tutorial.cxx
+++ b/Help/guide/tutorial/Step7/tutorial.cxx
@@ -20,13 +20,14 @@ int main(int argc, char* argv[])
     return 1;
   }
 
-  double inputValue = std::stod(argv[1]);
+  // convert input to double
+  const double inputValue = std::stod(argv[1]);
 
   // which square root function should we use?
 #ifdef USE_MYMATH
-  double outputValue = mysqrt(inputValue);
+  const double outputValue = mysqrt(inputValue);
 #else
-  double outputValue = sqrt(inputValue);
+  const double outputValue = sqrt(inputValue);
 #endif
 
   std::cout << "The square root of " << inputValue << " is " << outputValue