/in/foo.cc: In member function 'bool Dinic::Bfs()':
/in/foo.cc:61:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for(int i=0; i<G[Now].size(); i++) {
                 ~^~~~~~~~~~~~~~
/in/foo.cc: In member function 'double Dinic::Dfs(int, double)':
/in/foo.cc:77:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int& i=Current[Now]; i<G[Now].size(); i++) { //引用传边,直接从上一次考虑的弧增广
                            ~^~~~~~~~~~~~~~