foo.c: In function 'main':
foo.c:22:10: error: expected ';' before '}' token
   22 |  return 0
      |          ^
      |          ;
   23 | }
      | ~         
foo.c:17:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   17 |  scanf("%d",&a);
      |  ^~~~~~~~~~~~~~

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