Compilare: main.cpp: In function 'void solve(std::__cxx11::string, int)': main.cpp:96:23: warning: array subscript has type 'char' [-Wchar-subscripts] avail[root->letter].push_back(root); ^ main.cpp:100:40: warning: array subscript has type 'char' [-Wchar-subscripts] vector<trie*> elim = avail[s[i]]; ^ main.cpp:101:19: warning: array subscript has type 'char' [-Wchar-subscripts] avail[s[i]].clear(); ^ main.cpp:107:44: warning: array subscript has type 'char' [-Wchar-subscripts] avail[(next.second)->letter].push_back(next.second); ^