foo.cc: In function 'int main()':
foo.cc:68:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   68 |     scanf("%d %d", &n, &m);
      |     ~~~~~^~~~~~~~~~~~~~~~~
foo.cc:70:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   70 |         scanf("%d", &p[i]);
      |         ~~~~~^~~~~~~~~~~~~
foo.cc:77:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   77 |             scanf("%d", &a[i][j]);
      |             ~~~~~^~~~~~~~~~~~~~~~

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