foo.cc: In function 'int main()':
foo.cc:13:6: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   13 | scanf("%d",&t);
      | ~~~~~^~~~~~~~~
foo.cc:17:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   17 | scanf ("%d %d", &m, &n);
      | ~~~~~~^~~~~~~~~~~~~~~~~

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