diff --git a/education/software development/ECE1400/Chapter 14 Exercises.md b/education/software development/ECE1400/Chapter 14 Exercises.md
index 2d24f30..194bfa9 100644
--- a/education/software development/ECE1400/Chapter 14 Exercises.md	
+++ b/education/software development/ECE1400/Chapter 14 Exercises.md	
@@ -6,6 +6,9 @@
 ```c
 // C will fail, because `M` is defined.
 #ifndef M
+
+// E will fail, because `M` is defined
+#if !defined(M)
 ```
 
 ---