Compilare: main.cpp: In function 'void add(nod*, std::string&, int)': main.cpp:27:12: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 27 | if(poz == s.size()) | ~~~~^~~~~~~~~~~ main.cpp: In function 'void del(nod*, std::string&, int)': main.cpp:47:12: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 47 | if(poz == s.size()) | ~~~~^~~~~~~~~~~ main.cpp: In function 'int count(nod*, std::string&, int)': main.cpp:68:12: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 68 | if(pos == s.size()) | ~~~~^~~~~~~~~~~ main.cpp: In function 'int pref(nod*, std::string, int)': main.cpp:78:33: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 78 | if(node_tire == NULL or pos == s.size()) | ~~~~^~~~~~~~~~~