foo.cc: In function 'int main()':
foo.cc:44:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%lld",&n);
     ~~~~~^~~~~~~~~~~
foo.cc:51:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%lld%lld%lld%lld",&x[i],&y[i],&p,&k);
         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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