/in/foo.c: In function 'printyanghuisanjiao':
/in/foo.c:17:5: warning: 'main' is normally a non-static function [-Wmain]
   17 | int main()
      |     ^~~~
/in/foo.c:23:1: error: expected declaration or statement at end of input
   23 | }
      | ^
/in/foo.c: At top level:
/in/foo.c:17:5: warning: 'main' defined but not used [-Wunused-function]
   17 | int main()
      |     ^~~~