feat: add day 3

CMakeLists.txt

@@ -3,7 +3,21 @@ project(advent_of_code_2023 C)
 
 set(CMAKE_C_STANDARD 17)
 
+if(NOT CMAKE_BUILD_TYPE)
+    set(CMAKE_BUILD_TYPE Release)
+endif()
+
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -O2 -Wall -Wextra -Wpedantic -Werror")
+
+# Add address sanitizer on debug builds
+if(CMAKE_BUILD_TYPE MATCHES Debug AND NOT WIN32)
+    add_compile_options(-fsanitize=address)
+    add_link_options(-fsanitize=address)
+endif()
+
 add_executable(day_01 day_1.c input_handler.c)
 
 add_executable(day_02 day_2.c input_handler.c)
 target_link_libraries(day_02 m)
+
+add_executable(day_03 day_3.c input_handler.c)