Compilare: main.cpp: In function 'void insert(trie*, std::string)': main.cpp:31:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 31 | for (int i = 0; i < w.size(); i++) | ~~^~~~~~~~~~ main.cpp: In function 'int src(trie*, std::string)': main.cpp:49:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 49 | for (int i = 0; i < w.size(); i++) | ~~^~~~~~~~~~ main.cpp: In function 'void erase(trie*, std::string)': main.cpp:64:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 64 | for (int i = 0; i < w.size(); i++) | ~~^~~~~~~~~~ main.cpp: In function 'int maxPref(trie*, std::string)': main.cpp:109:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 109 | for (int i = 0; i < w.size(); i++) | ~~^~~~~~~~~~