Compilare: main.cpp: In function 'int lung(std::string, char)': main.cpp:23:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 23 | for(int i = 0; i < s.size(); i++) | ~~^~~~~~~~~~ main.cpp: In function 'int ok(std::string)': main.cpp:34:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 34 | for(int i = 0; i < s.size(); i++) | ~~^~~~~~~~~~ main.cpp:36:26: 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 j = i; j < s.size(); j++) | ~~^~~~~~~~~~ main.cpp: In function 'void gen(int, std::string, int, int)': main.cpp:49:20: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare] 49 | if (s.length() == n) | ~~~~~~~~~~~^~~~ main.cpp: In function 'int main()': main.cpp:65:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::__cxx11::basic_string<char> >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 65 | for(int i = 0; i < v.size(); i++) | ~~^~~~~~~~~~