Compilare: main.cpp: In function 'void add(std::string)': main.cpp:22:27: 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 < word.size() && p != NULL; i++) | ~~^~~~~~~~~~~~~ main.cpp: In function 'void del(nod*, std::string, int)': main.cpp:38:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 38 | if (i < word.size() - 1) | ~~^~~~~~~~~~~~~~~~~ main.cpp: In function 'int count(std::string)': main.cpp:65:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 65 | for (int i = 0; i < word.size() && p != NULL; i++) | ~~^~~~~~~~~~~~~ main.cpp: In function 'int longestPrefix(std::string)': main.cpp:82:27: 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 < word.size() && p != NULL; i++) | ~~^~~~~~~~~~~~~