foo.c: In function 'main':
foo.c:23:13: warning: missing terminating " character
   23 |      printf("%d,%d,a,c);
      |             ^
foo.c:23:13: error: missing terminating " character
   23 |      printf("%d,%d,a,c);
      |             ^~~~~~~~~~~~
foo.c:24:6: error: expected expression before 'return'
   24 |      return 0
      |      ^~~~~~
foo.c:24:14: error: expected ';' before '}' token
   24 |      return 0
      |              ^
      |              ;
   25 | }
      | ~             

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