foo.cc: In function 'int main()':
foo.cc:35:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d",&n);
     ~~~~~^~~~~~~~~
foo.cc:36:31: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     for(int i=1;i<=n;i++)scanf("%d%d",&p[i].x,&p[i].y);
                          ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

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