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@@ -1,8 +1,8 @@
 ## To Do ##
 
 * (01) Basic Concepts I -> Catastrofic Cancellation (loss of significance)
-* (09) Code Organization and Conventions -> optimize the compile time
 * (11) Advanced Concepts -> volatile keyword
 * (12) Code Optimization
+* (12) Code Optimization -> optimize the compile time
 * (B) Appendix
 * C++17