foo.cc: In function 'int main()':
foo.cc:13:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   13 |  scanf("%d",&n);
      |  ~~~~~^~~~~~~~~
foo.cc:16:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   16 |   scanf("%lf",&a[i].x);
      |   ~~~~~^~~~~~~~~~~~~~~

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