/in/foo.cc: In function 'void dfs(long long int)':
/in/foo.cc:14:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<a[x].l.size();i++)
              ~^~~~~~~~~~~~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:33:33: warning: variable 'e' set but not used [-Wunused-but-set-variable]
   int m,ma=INT_MIN,mi=INT_MAX,s,e,fd,ans;
                                 ^
/in/foo.cc:33:35: warning: unused variable 'fd' [-Wunused-variable]
   int m,ma=INT_MIN,mi=INT_MAX,s,e,fd,ans;
                                   ^~