foo.cc: In function 'int main()':
foo.cc:8:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d%d", &n, &m, &q);
  ~~~~~^~~~~~~~~~~~~~~~~~~~~~
foo.cc:15:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("l%d %c l%d", &l1,&op, &l2);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:57:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("l%d l%d", &l1, &l2);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~

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