Compilare: main.cpp: In function 'bool dfs(long long int, long long int, std::vector<std::vector<long long int> >&, std::vector<long long int>&)': main.cpp:14:16: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 14 | for (i=0; i<v1[a].size(); i++) | ~^~~~~~~~~~~~~ main.cpp: In function 'std::vector<std::vector<long long int> > fid(long long int, std::vector<std::vector<long long int> >&)': main.cpp:33:16: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::vector<long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 33 | for (i=0; i<a.size(); i++) | ~^~~~~~~~~ main.cpp: In function 'int main()': main.cpp:73:16: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::vector<long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 73 | for (i=0; i<r.size(); i++){ | ~^~~~~~~~~ main.cpp:74:20: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 74 | for (j=0; j<r[i].size(); j++) | ~^~~~~~~~~~~~