foo.cc: In function 'int main()':
foo.cc:9:6: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    9 | scanf("%d%d%d", &n, &m, &p);
      | ~~~~~^~~~~~~~~~~~~~~~~~~~~~
foo.cc:12:16: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   12 | int x, y; scanf("%d%d", &x, &y);
      |           ~~~~~^~~~~~~~~~~~~~~~

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