Compilare: user.cpp: In function ‘void back_add(int, long long int)’: user.cpp:47:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (pas == divs[add_id].size()) { ^ user.cpp: In function ‘void back_solve(int, long long int, bool)’: user.cpp:74:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (pas == prim.size()) { ^ user.cpp: In function ‘int main()’: user.cpp:106:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("porcjoc.in","r",stdin); ^ user.cpp:107:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("porcjoc.out","w",stdout); ^ user.cpp:113:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:115:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &v, &p); ^