Compilare: main.cpp: In function 'void solve(int, std::vector<std::vector<int> >&, std::vector<int>&)': main.cpp:13:27: 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 < master[node].size(); i++) | ~~^~~~~~~~~~~~~~~~~~~~~ main.cpp: In function 'void DFS(int, std::vector<std::vector<int> >&, std::vector<bool>&)': main.cpp:24:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 24 | for (int i = 0; i < master[node].size(); i++) | ~~^~~~~~~~~~~~~~~~~~~~~ main.cpp: In function 'void set_union(std::vector<bool>&, std::vector<bool>&)': main.cpp:35:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<bool>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 35 | for (int i = 0; i < A.size(); i++) | ~~^~~~~~~~~~ main.cpp: In function 'bool verify(std::vector<bool>&)': main.cpp:45:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<bool>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 45 | for (int i = 0; i < A.size(); i++) | ~~^~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:80:35: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<bool>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 80 | for (int i = 0; i < freq.size(); i++) | ~~^~~~~~~~~~~~~