Compilare: user.cpp: In function ‘int main()’: user.cpp:45:30: warning: format ‘%lu’ expects argument of type ‘long unsigned int’, but argument 2 has type ‘std::vector<int>::size_type {aka unsigned int}’ [-Wformat=] printf("%lu\n", v.size() - 1); ^ user.cpp:46:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < v.size() - 1; i++) ^ user.cpp:24:6: warning: unused variable ‘num_phrases’ [-Wunused-variable] int num_phrases = 0; ^ user.cpp:14:30: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("nc.in", "r", stdin); ^ user.cpp:15:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("nc.out", "w", stdout); ^