foo.cc: In function 'int main()':
foo.cc:12:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   12 |     scanf("%d\n+",&n);
      |     ~~~~~^~~~~~~~~~~~
foo.cc:14:31: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   14 |     for(int i=0;i<n;i++) scanf(" %c",&cv),u[i]=cv;
      |                          ~~~~~^~~~~~~~~~~
foo.cc:17:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   17 |         scanf("\n%c",&cv);
      |         ~~~~~^~~~~~~~~~~~
foo.cc:20:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   20 |             scanf(" %s",tmp);
      |             ~~~~~^~~~~~~~~~~

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