Compilare: main.cpp: In function 'int32_t main()': main.cpp:23:19: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 23 | for (i = 0; i < a.size(); i++) | ~~^~~~~~~~~~ main.cpp:42:26: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 42 | for (i = a.size(); i < b.size(); i++) | ~~^~~~~~~~~~