Compilare: main.cpp: In member function 'void Task::show_matrix()': main.cpp:33:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < N; i++) { ~~^~~ main.cpp:35:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < matrix[i].size(); j++) { ~~^~~~~~~~~~~~~~~~~~ main.cpp: In member function 'void Task::DFS_UTIL(int, std::vector<bool>&)': main.cpp:45:26: warning: unused variable 'x' [-Wunused-variable] for (auto const &x: matrix[node]) { ^ main.cpp: In member function 'int Task::DFS()': main.cpp:55:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i <= N; i++) { ~~^~~~