foo.cc: In function 'int main()':
foo.cc:23:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   23 |     scanf("%d%d%d", &n, &m, &q);
      |     ~~~~~^~~~~~~~~~~~~~~~~~~~~~
foo.cc:43:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   43 |         scanf("%d%d", &a, &b);
      |         ~~~~~^~~~~~~~~~~~~~~~

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