foo.cc: In function 'int main()':
foo.cc:35:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   35 |  scanf("%d",&n);
      |  ~~~~~^~~~~~~~~
foo.cc:36:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   36 |  for (int i=1;i<=n;i++) scanf("%d%d",&a[i].x,&a[i].y);
      |                         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

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