foo.cc: In function 'int main()':
foo.cc:41:18: warning: unused variable 'p' [-Wunused-variable]
   41 |     int m, n, k, p;
      |                  ^
foo.cc:44:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   44 |         scanf("%d", &k);
      |         ~~~~~^~~~~~~~~~
foo.cc:47:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   47 |             scanf("%d%d", &a[i].x, &a[i].y);
      |             ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

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