Arduino:1.8.13 (Windows 10), 开发板:"Arduino Nano, ATmega328P (Old Bootloader)"
E:\arduino\ANJIAN\ANJIAN.ino: In function 'void loop()':
ANJIAN:23:4: error: case label '2' not within a switch statement
case 2:
^~~~
ANJIAN:25:4: error: break statement not within loop or switch
break;
^~~~~
exit status 1
case label '2' not within a switch statement
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