Compilare: user.cpp: In function ‘void add(trie*, int)’: user.cpp:38:22: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(!nod->f[a[poz]]) ^ user.cpp:39:22: warning: array subscript has type ‘char’ [-Wchar-subscripts] nod->f[a[poz]] = new trie; ^ user.cpp:40:22: warning: array subscript has type ‘char’ [-Wchar-subscripts] add(nod->f[a[poz]], poz + 1); ^ user.cpp: In function ‘void del(trie*, int)’: user.cpp:50:22: warning: array subscript has type ‘char’ [-Wchar-subscripts] del(nod->f[a[poz]], poz + 1); ^ user.cpp: In function ‘int nrap(trie*, int)’: user.cpp:59:30: warning: array subscript has type ‘char’ [-Wchar-subscripts] return nrap(nod->f[a[poz]], poz + 1); ^ user.cpp: In function ‘int pref(trie*, int)’: user.cpp:68:33: warning: array subscript has type ‘char’ [-Wchar-subscripts] int val = pref(nod->f[a[poz]], poz + 1); ^ user.cpp: In function ‘int main()’: user.cpp:76:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("trie.in", "r", stdin); ^ user.cpp:77:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("trie.out", "w", stdout); ^