Compilare: main.cpp: In function 'void add(std::string)': main.cpp:15:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 15 | for(int i = 0; i < s.size(); i++){ | ~~^~~~~~~~~~ main.cpp:17:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 17 | for(int j = 0; j < v[p].second.size(); j++){ | ~~^~~~~~~~~~~~~~~~~~~~