/in/foo.cc:8:1: error: ISO C++ forbids declaration of 'dfs' with no type [-fpermissive]
    8 | dfs(int now,int fa,int dep){
      | ^~~
/in/foo.cc: In function 'int dfs(int, int, int)':
/in/foo.cc:11:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   11 |         for(int i=0;i<ed[now].size();i++)
      |                     ~^~~~~~~~~~~~~~~
/in/foo.cc:13:1: warning: no return statement in function returning non-void [-Wreturn-type]
   13 | }
      | ^