Compilare: user.cpp: In function ‘long long int secv(int)’: user.cpp:19:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (x < h.size()) ^ user.cpp: In function ‘void solve()’: user.cpp:33:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&n,&l,&u); ^ user.cpp:34:46: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(int i=1;i<=n;++i) scanf("%lld",&v[i]); ^ user.cpp: In function ‘int main()’: user.cpp:41:34: 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:42:36: 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); ^