Compilare: user.cpp: In constructor ‘trie::trie()’: user.cpp:35:30: warning: passing NULL to non-pointer argument 2 of ‘void* memset(void*, int, size_t)’ [-Wconversion-null] memset(fiu,NULL,sizeof(fiu)); ^ user.cpp: In function ‘int search_trie(trie*, int, int)’: user.cpp:92:16: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(nod->fiu[ch] == NULL) return 0; ^ user.cpp:93:32: warning: array subscript has type ‘char’ [-Wchar-subscripts] return search_trie(nod->fiu[ch], pos+1, sim); ^ user.cpp: In function ‘void insert_trie(trie*, int)’: user.cpp:98:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(pos == s.size()) ^ user.cpp:102:16: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(nod->fiu[ch] == NULL) { ^ user.cpp:103:14: warning: array subscript has type ‘char’ [-Wchar-subscripts] nod->fiu[ch]=new trie; ^ user.cpp:106:25: warning: array subscript has type ‘char’ [-Wchar-subscripts] insert_trie(nod->fiu[ch], pos+1); ^