foo.cc: In function 'int main()':
foo.cc:12:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   12 |     scanf("%d%d", &x, &y);
      |     ~~~~~^~~~~~~~~~~~~~~~
foo.cc:18:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   18 |             scanf("%d", &a[i][j]);
      |             ~~~~~^~~~~~~~~~~~~~~~

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