Compilare: user.cpp: In function ‘void bck(int, bitsetbun, int)’: user.cpp:37:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < primes[pas].size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:58:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("numerologie.in", "r", stdin); ^ user.cpp:59:44: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("numerologie.out", "w", stdout); ^ user.cpp:62:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &N, &M); ^ user.cpp:64:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &v[i]); ^ user.cpp:69:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &x); ^