foo.cc: In function 'int main()':
foo.cc:9:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    9 |     scanf("%d%d%d",&n,&m,&q);
      |     ~~~~~^~~~~~~~~~~~~~~~~~~
foo.cc:29:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   29 |         scanf("%d%d",&l,&r);
      |         ~~~~~^~~~~~~~~~~~~~

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