Compilare: user.cpp: In function ‘long long int nrsec(long int)’: user.cpp:62:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(R<=n) ^ user.cpp: In function ‘int main()’: user.cpp:82:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(long i=1;i<=n;i++) ^ user.cpp:77:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("secv5.in","r",stdin); ^ user.cpp:78:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("secv5.out","w",stdout); ^ user.cpp:80:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lu%lu%lu",&n,&l,&u); ^ user.cpp:83:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lu",&v[i]); ^