foo.cc: In function 'int main()':
foo.cc:10:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   10 |  scanf("%d%d", &t, &k);
      |  ~~~~~^~~~~~~~~~~~~~~~
foo.cc:19:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   19 |   scanf("%d%d", &n, &m);
      |   ~~~~~^~~~~~~~~~~~~~~~

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