foo.cc: In function 'int main()':
foo.cc:26:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   26 |     scanf("%d %d %d", &n, &m, &q);
      |     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:27:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   27 |     scanf(" %s %s", txt, pat);
      |     ~~~~~^~~~~~~~~~~~~~~~~~~~
foo.cc:54:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   54 |         scanf("%d %d", &l, &r);
      |         ~~~~~^~~~~~~~~~~~~~~~~

[Hydro](https://hydro.ac)提供评测服务