foo.cc: In function 'void dfs(int, int)':
foo.cc:12:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   12 |     for (int i = 0; i < G[u].size(); ++i) {
      |                     ~~^~~~~~~~~~~~~
foo.cc: In function 'void dfs2(int, int)':
foo.cc:32:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   32 |     for (int i = 0; i < G[u].size(); ++i) {
      |                     ~~^~~~~~~~~~~~~

正在同步测试数据，请稍后
Found 10 testcases.
[Hydro](https://hydro.ac)提供评测服务