foo.cc: In function 'int main()':
foo.cc:7:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    7 |  scanf("%d %d %d",&n,&m,&q);
      |  ~~~~~^~~~~~~~~~~~~~~~~~~~~
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",&l,&r);
      |   ~~~~~^~~~~~~~~~~~~~~

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