foo.cc: In function ‘int dfs(int)’:
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<g[x].size();i++)
      |                     ~^~~~~~~~~~~~
foo.cc: In function ‘int main()’:
foo.cc:53:21: warning: unused variable ‘ans’ [-Wunused-variable]
   53 |                 int ans=dfs(1);
      |                     ^~~