Compilare: main.cpp: In function 'void dfs(int)': main.cpp:13:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 13 | for ( int i = 0; i < adj[u].size(); ++i ) { | ~~^~~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:43:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 43 | for ( int i = 0; i < sol.size(); ++i ) { | ~~^~~~~~~~~~~~