Compilare: main.cpp: In function 'int main()': main.cpp:24:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 24 | for(int i = 1; i < a.size(); i++) | ~~^~~~~~~~~~ main.cpp:40:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 40 | for(int i = 0; i < sol.size(); i++) | ~~^~~~~~~~~~~~