Compilare: user.cpp: In function ‘void solve(long long int)’: user.cpp:44:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int it=0;it<vNrPrime.size();it++) ^ user.cpp: In function ‘int main()’: user.cpp:64:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ssnd.in","r",stdin); ^ user.cpp:65:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ssnd.out","w",stdout); ^ user.cpp:69:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&t); ^ user.cpp:72:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lld",&nr); ^