Compilare: user.cpp: In function ‘int main()’: user.cpp:28:11: warning: unused variable ‘flag’ [-Wunused-variable] bool flag = true; ^ user.cpp:34:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < v.size(); i++) { ^ user.cpp:18:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("suman.in","r",stdin); ^ user.cpp:19:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("suman.out","w",stdout); ^