foo.cc: In function 'int main()':
foo.cc:40:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   40 |     scanf("%d%d", &T, &k);
      |     ~~~~~^~~~~~~~~~~~~~~~
foo.cc:45:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   45 |         scanf("%d%d", &n, &m);
      |         ~~~~~^~~~~~~~~~~~~~~~

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