Compilare: main.cpp: In function 'void add(std::string, std::vector<nod>&)': main.cpp:22:25: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 22 | for ( int i = 0 ; i < s.size() ; i ++ ) | ~~^~~~~~~~~~ main.cpp: In function 'int cauta(std::string, std::vector<nod>&)': main.cpp:46:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 46 | for (int i = 0 ; i < s.size() ; i ++ ) | ~~^~~~~~~~~~ main.cpp: In function 'void sterg(std::string, std::vector<nod>&)': main.cpp:67:25: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 67 | for ( int i = 0 ; i < s.size() ; i ++ ) | ~~^~~~~~~~~~ main.cpp: In function 'int prefix(std::string, std::vector<nod>&)': main.cpp:82:25: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 82 | for ( int i = 0 ; i < s.size() ; i ++ ) | ~~^~~~~~~~~~