/in/foo.cc: In function 'void clear_all()':
/in/foo.cc:26:54: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
   26 |     for(int i=0;i<=ctt;i++){clear(v[i]);lf[i]=line[i]=siz[i]=0;}
      |                                               ~~~~~~~^~~~~~~~~
/in/foo.cc: In function 'void dfs1(int)':
/in/foo.cc:33:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   33 |     for(int i=0;i<v[x].size();i++)
      |                 ~^~~~~~~~~~~~