foo.cc: In function 'int main()':
foo.cc:9:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    9 |  scanf("%d%d%d",&n,&m,&k);
      |  ~~~~~^~~~~~~~~~~~~~~~~~~
foo.cc:10:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   10 |  for (int i=1;i<=n;i++) scanf("%d%d",&x[i],&y[i]);
      |                         ~~~~~^~~~~~~~~~~~~~~~~~~~
foo.cc:16:21: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   16 |   int xx,yy,zz;scanf("%d%d%d",&xx,&yy,&zz);
      |                ~~~~~^~~~~~~~~~~~~~~~~~~~~~

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