Compilare: user.cpp: In function ‘bool detail::Delete(TrieNode*, const string&, int)’: user.cpp:42:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (indexInWord == word.length()) ^ user.cpp: In function ‘int detail::CountLongestCommonPrefix(const TrieNode*, const string&, int, int)’: user.cpp:61:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (indexInWord == word.length()) ^ user.cpp: In function ‘void detail::AddWordOccurrence(TrieNode*, const string&, int)’: user.cpp:75:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (indexInWord == word.length()) ^ user.cpp: In function ‘int detail::CountOccurrences(TrieNode*, const string&, int)’: user.cpp:98:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (indexInWord == word.length()) ^ user.cpp: In function ‘int main()’: user.cpp:157:32: 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:158:34: 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); ^ user.cpp:159:24: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(line, 32, stdin); ^ user.cpp:170:25: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(line, 32, stdin); ^