Compilare: user.cpp: In function ‘bool detail::Delete(TrieNode&, const string&, int)’: user.cpp:29:34: 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:49:34: 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:64:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (indexInWord == word.length()) ^ user.cpp: In function ‘int detail::CountOccurrences(const TrieNode&, const string&, int)’: user.cpp:88:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (indexInWord == word.length()) ^ user.cpp: In function ‘int main()’: user.cpp:148:32: 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:149:34: 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:150:24: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(line, 32, stdin); ^ user.cpp:161:25: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(line, 32, stdin); ^