Eroare de compilare: user.cpp: In function ‘void deleteW(char*, int)’: user.cpp:37:19: warning: variable ‘prev’ set but not used [-Wunused-but-set-variable] Trie *t = root, *prev; ^ user.cpp: In function ‘int main()’: user.cpp:81:30: error: ‘strlen’ was not declared in this scope case 0: insertW(w, strlen(w)); break; ^ user.cpp:74:32: 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:75:34: 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); ^