Compilare: user.cpp: In function ‘int solve(int)’: user.cpp:154:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] ok &= e.size() == lim; ^ user.cpp:156:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] ok &= it.size() == D - 1; ^ user.cpp: In function ‘int main()’: user.cpp:250:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("divizori2.in","r",stdin); ^ user.cpp:251:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("divizori2.out","w",stdout); ^