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("%4d%2d%2d", &y1, &m1, &d1);
      |     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
foo.cc:30:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   30 |     scanf("%4d%2d%2d", &y2, &m2, &d2);
      |     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

Found 5 testcases.
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