foo.cc: In function 'int main()':
foo.cc:49:8: warning: unused variable 'j' [-Wunused-variable]
  int i,j,k;
        ^
foo.cc:49:10: warning: unused variable 'k' [-Wunused-variable]
  int i,j,k;
          ^
foo.cc:48:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&N);
  ~~~~~^~~~~~~~~
foo.cc:52:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d",&X[i],&Y[i]);
   ~~~~~^~~~~~~~~~~~~~~~~~~~

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