arboras.cpp: In function 'void build_chain()':
arboras.cpp:83:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   83 |         for (int i = 0; i < ver.size(); i ++)
      |                         ~~^~~~~~~~~~~~
arboras.cpp: In function 'void update_edge(int, ll)':
arboras.cpp:361:33: warning: variable 'sad' set but not used [-Wunused-but-set-variable]
  361 |                 pair < ll, ll > sad = get_element(par[v]);
      |                                 ^~~