Compilare: main.cpp: In function 'void add(Tnode*, std::string, int)': main.cpp:26:10: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 26 | if(i == s.size()){ | ~~^~~~~~~~~~~ main.cpp: In function 'int del(Tnode*, std::string, int)': main.cpp:40:10: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 40 | if(i == s.size()) | ~~^~~~~~~~~~~ main.cpp: In function 'int apar(Tnode*, std::string, int)': main.cpp:68:10: 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(i == s.size()) | ~~^~~~~~~~~~~ main.cpp: In function 'int pref(Tnode*, std::string, int)': main.cpp:81:10: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 81 | if(i == s.size()) | ~~^~~~~~~~~~~