foo.c:13:1: error: expected identifier or '(' before 'return'
   13 | return 0;
      | ^~~~~~
foo.c: In function 'main':
foo.c:6:1: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    6 | scanf("%d",&n);
      | ^~~~~~~~~~~~~~

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