Compilare: main.cpp: In function 'void _z(const std::string&)': main.cpp:27:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 27 | for(int i = 1; i < s.size(); i ++) | ~~^~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:57:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 57 | for(int i = 0; i < s.size(); i ++) | ~~^~~~~~~~~~ main.cpp:59:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 59 | if(z[i] == a.size()) | ~~~~~^~~~~~~~~~~ main.cpp:69:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 69 | for(int i = 0; i < s.size(); i ++) | ~~^~~~~~~~~~ main.cpp:71:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 71 | if(z[i] == a.size()) | ~~~~~^~~~~~~~~~~