Compilare: user.cpp: In function ‘int main()’: user.cpp:18:59: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(k=0; k<hs[(s-v[i]-v[j])%MOD].size(); ++k) ^ user.cpp:8:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("oite.in","r",stdin); ^ user.cpp:9:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("oite.out","w",stdout); ^ user.cpp:10:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&s); ^ user.cpp:12:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&v[i]); ^