foo.cc:18:1: error: expected unqualified-id before 'return'
   18 | return 0;
      | ^~~~~~
foo.cc: In function 'int main()':
foo.cc:6:6: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    6 | scanf("%d%d",&t,&n);
      | ~~~~~^~~~~~~~~~~~~~
foo.cc:9:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    9 |     scanf("%d",&v[i]);
      |     ~~~~~^~~~~~~~~~~~

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