/in/foo.cc: In function 'int main()':
/in/foo.cc:74:13: warning: unused variable 'temp' [-Wunused-variable]
         ull temp = uf.find(i);
             ^~~~
/in/foo.cc:100:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i=0;i<v.size();i++)cout<<v[i]<<" ";
                 ~^~~~~~~~~