C:\Users\sec\AppData\Local\Temp\arduino_modified_sketch_533351\sketch_jun10a.ino:4:0: warning: "F" redefined

 #define F 349 // 파 

 ^

In file included from C:\Users\sec\AppData\Local\Arduino15\packages\arduino\hardware\avr\1.6.21\cores\arduino/Arduino.h:231:0,

                 from sketch\sketch_jun10a.ino.cpp:1:

C:\Users\sec\AppData\Local\Arduino15\packages\arduino\hardware\avr\1.6.21\cores\arduino/WString.h:38:0: note: this is the location of the previous definition

 #define F(string_literal) (reinterpret_cast<const __FlashStringHelper *>(PSTR(string_literal)))

 ^

C:\Users\sec\AppData\Local\Temp\ccC4fiiS.ltrans0.ltrans.o: In function `main':

C:\Users\sec\AppData\Local\Arduino15\packages\arduino\hardware\avr\1.6.21\cores\arduino/main.cpp:43: undefined reference to `setup'

C:\Users\sec\AppData\Local\Arduino15\packages\arduino\hardware\avr\1.6.21\cores\arduino/main.cpp:46: undefined reference to `loop'

collect2.exe: error: ld returned 1 exit status

exit status 1
보드 Arduino/Genuino Uno 컴파일 에러.

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