Compilare: main.cpp: In member function 'void Nod::add(const std::string&, int)': main.cpp:29:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 29 | if (i == s.size()) | ~~^~~~~~~~~~~ main.cpp: In member function 'void Nod::mark(const std::string&, int)': main.cpp:39:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 39 | if (i == s.size()) | ~~^~~~~~~~~~~ main.cpp: In member function 'void Nod::remove()': main.cpp:48:16: warning: suggest explicit braces to avoid ambiguous 'else' [-Wdangling-else] 48 | if (kids[i] != NULL) | ^ main.cpp: In function 'int main()': main.cpp:86:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 86 | for (int i = 0; i < s.size(); i++) | ~~^~~~~~~~~~ main.cpp:91:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 91 | for (int i = 0; i < s.size(); i++) | ~~^~~~~~~~~~ main.cpp:99:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 99 | for (int i = 0; i < s.size(); i++) | ~~^~~~~~~~~~