Compilare: user.cpp: In function ‘void query(Trie*, char*)’: user.cpp:66:35: warning: array subscript has type ‘char’ [-Wchar-subscripts] node = node->son[node->best_son]; ^ user.cpp: In function ‘int main()’: user.cpp:82:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("fbsearch.out", "w", stdout); ^ user.cpp:84:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &tests); ^ user.cpp:88:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &N, &M); ^ user.cpp:90:13: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(line); ^ user.cpp:92:26: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(W[i], 64, stdin); ^ user.cpp:97:26: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(line, 64, stdin); ^ /tmp/ccVumBpR.o: In function `main': user.cpp:(.text.startup+0x121): warning: the `gets' function is dangerous and should not be used.