Compilare: main.cpp: In function 'int main()': main.cpp:15:15: 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=1;i<a.size();i++) | ~^~~~~~~~~ main.cpp:17:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 17 | for(int i=0;i<a.size();i++) | ~^~~~~~~~~ main.cpp:19:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 19 | for(int i=0;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=a.size();i<b.size();i++) | ~^~~~~~~~~