Compilare: main.cpp: In function 'void dfs(int)': main.cpp:21:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 21 | for (int i = 0; i < fii[nod].size(); ++i) { | ~~^~~~~~~~~~~~~~~~~ main.cpp: In function 'void post_st(int)': main.cpp:29:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 29 | for (int i = 0; i < fii[nod].size(); ++i) | ~~^~~~~~~~~~~~~~~~~