Compilare: main.cpp: In function 'void add(trie*, int)': main.cpp:26:12: 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(idx == s.length()){ | ~~~~^~~~~~~~~~~~~ main.cpp: In function 'void del(trie*, int)': main.cpp:42:12: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 42 | if(idx == s.length()){ | ~~~~^~~~~~~~~~~~~ main.cpp: In function 'int nrAp(trie*, int)': main.cpp:53:12: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 53 | if(idx == s.length()) | ~~~~^~~~~~~~~~~~~ main.cpp: In function 'int pref(trie*, int)': main.cpp:65:12: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 65 | if(idx == s.length()) | ~~~~^~~~~~~~~~~~~