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("%s",b[i]);
      |     ~~~~~^~~~~~~~~~~
foo.cc:13:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   13 |     scanf("%s",a[i]);
      |     ~~~~~^~~~~~~~~~~

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