Compilare: user.cpp: In function ‘int main()’: user.cpp:58:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < v.size(); i++) ^ user.cpp:37:30: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("oz.in", "r", stdin); ^ user.cpp:38:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("oz.out", "w", stdout); ^