/in/foo.cc: In function 'int main()':
/in/foo.cc:39:49: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  for(int i=1;i<=n;i++)scanf("%d",&a[i]),ord[i]=i;
                                                 ^
/in/foo.cc:50:37: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   int x,y,k;scanf("%d%d%d",&x,&y,&k);
                                     ^