foo.cc: In function 'int main()':
foo.cc:32:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   32 |  scanf("%d%d%d",&n,&m,&k);
      |  ~~~~~^~~~~~~~~~~~~~~~~~~
foo.cc:33:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   33 |  for(int i=1;i<=n;i++) scanf("%d%d",&a[i],&b[i]);
      |                        ~~~~~^~~~~~~~~~~~~~~~~~~~
foo.cc:37:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   37 |   scanf("%d%d",&x,&y);
      |   ~~~~~^~~~~~~~~~~~~~

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