foo.cc: In function 'int main()':
foo.cc:40:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   40 |  scanf("%d%d%d",&n,&s,&t);
      |  ~~~~~^~~~~~~~~~~~~~~~~~~
foo.cc:41:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   41 |  for(int i=1;i<=n;i++) scanf("%d",&dis[i]);
      |                        ~~~~~^~~~~~~~~~~~~~

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