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:26:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 26 | for(int i = 1; i <= b.size(); i++) | ~~^~~~~~~~~~~ main.cpp:29:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 29 | for(int i = 1; i <= a.size(); i++) | ~~^~~~~~~~~~~ main.cpp:31:29: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 31 | for(int i = a.size(); i <= b.size(); i++) | ~~^~~~~~~~~~~