Compilare: main.cpp: In function 'int main()': main.cpp:108:23: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<ob>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 108 | for (j = 0; j < it->second.size(); j++) | ~~^~~~~~~~~~~~~~~~~~~ main.cpp:151:23: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<ob2>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 151 | for (j = 0; j < it2->second.size(); j++) | ~~^~~~~~~~~~~~~~~~~~~~