Compilare: main.cpp: In function 'trie* get_nod(trie*, std::__cxx11::basic_string<char>::iterator)': main.cpp:27:18: warning: array subscript has type 'char' [-Wchar-subscripts] if(nod->fiu[*it] == 0){ ^ main.cpp:29:17: warning: array subscript has type 'char' [-Wchar-subscripts] nod->fiu[*it] = new trie; ^ main.cpp:31:30: warning: array subscript has type 'char' [-Wchar-subscripts] return get_nod(nod->fiu[*it], it + 1); ^ main.cpp: In function 'int main()': main.cpp:54:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < s.size(); j++) ~~^~~~~~~~~~ main.cpp:80:19: warning: array subscript has type 'char' [-Wchar-subscripts] if(nod->fiu[ch] != 0) ^ main.cpp:81:24: warning: array subscript has type 'char' [-Wchar-subscripts] nod = nod->fiu[ch]; ^