foo.cc: In function 'int main()':
foo.cc:23:31: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   23 |  for (i = 0; i < n; i++) scanf("%lld", &v[i]);
      |                          ~~~~~^~~~~~~~~~~~~~~
foo.cc:26:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   26 |   scanf("%lld%lld", &t[i].l, &t[i].r);
      |   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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