foo.cc: In function 'int main()':
foo.cc:10:11: warning: unused variable 'j' [-Wunused-variable]
   10 |   int E,n,j; cin>>E>>n;
      |           ^
foo.cc:15:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   15 |    scanf("%d%d",&x,&y);
      |    ~~~~~^~~~~~~~~~~~~~

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