Compilare: main.cpp: In function 'void upd(Node*, int, int)': main.cpp:31:11: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 31 | if( poz == s.size() ) | ~~~~^~~~~~~~~~~ main.cpp: In function 'void del(Node*, int, int)': main.cpp:48:11: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 48 | if( poz == s.size() || node->child[s[poz]-'a'] == nullptr ) | ~~~~^~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:66:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 66 | for( j = 0; j < s.size(); j++ ) | ~~^~~~~~~~~~ main.cpp:72:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 72 | for( j = 0; j < s.size(); j++ ) | ~~^~~~~~~~~~