Compilare: main.cpp: In function 'int main()': main.cpp:33:25: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 33 | for ( int i = 0 ; i < a.size() ; ++ i ) | ~~^~~~~~~~~~ main.cpp:36:32: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 36 | for ( int i = a.size() ; i < b.size() ; ++ i ) | ~~^~~~~~~~~~