Compilare: main.cpp: In constructor 'trie::trie()': main.cpp:17:18: warning: array subscript has type 'char' [-Wchar-subscripts] nxt[i] = NULL; ^ main.cpp: In function 'void add(trie*, short int, short int)': main.cpp:28:33: warning: array subscript has type 'char' [-Wchar-subscripts] if( nod->nxt[ cod[ s[a] ] ] == NULL ){ ^ main.cpp:29:33: warning: array subscript has type 'char' [-Wchar-subscripts] nod->nxt[ cod[ s[a] ] ] = new trie; ^ main.cpp:32:34: warning: array subscript has type 'char' [-Wchar-subscripts] add( nod->nxt[ cod[ s[a] ] ], a + 1, b ); ^ main.cpp: In function 'bool del(trie*&, short int, short int)': main.cpp:40:38: warning: array subscript has type 'char' [-Wchar-subscripts] if( del( nod->nxt[ cod[ s[a] ] ], a + 1, b ) == true ) ^ main.cpp: In function 'void dfs(trie*)': main.cpp:55:23: warning: array subscript has type 'char' [-Wchar-subscripts] if( nod->nxt[i] == NULL ) ^ main.cpp:57:24: warning: array subscript has type 'char' [-Wchar-subscripts] dfs( nod->nxt[i] ); ^ main.cpp: In function 'int main()': main.cpp:75:14: warning: array subscript has type 'char' [-Wchar-subscripts] cod[i] = val++; ^ main.cpp:77:14: warning: array subscript has type 'char' [-Wchar-subscripts] cod[i] = val++; ^ main.cpp:79:14: warning: array subscript has type 'char' [-Wchar-subscripts] cod[i] = val++; ^