Compilare: main.cpp: In function 'int main()': main.cpp:56:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 56 | for (i = 0; i < it->second.size(); i++) | ~~^~~~~~~~~~~~~~~~~~~ main.cpp:62:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 62 | if (i + 1 < it->second.size()) | ~~~~~~^~~~~~~~~~~~~~~~~~~