Update build commands in README.md

README.md

@@ -9,13 +9,13 @@ Make sure you have a compiler (MSVC or GCC), CMake, and make/ninja installed.
 If you're using make to build the project, run the following commands:
 1. `mkdir build`
 2. `cd build`
-3. `cmake .. -G "Unix Makefiles"`
+3. `cmake .. -DCMAKE_BUILD_TYPE=Release -G "Unix Makefiles"`
 4. `make -j <number of threads>`
 
 If you're using ninja to build the project, run the following commands:
 1. `mkdir build`
 2. `cd build`
-3. `cmake .. -G Ninja`
+3. `cmake .. -DCMAKE_BUILD_TYPE=Release -G Ninja`
 4. `ninja`
 
 ## Directory structure