Compilare: user.cpp: In function ‘void desc(long long int)’: user.cpp:14:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i<prime.size() && d*d<=x) ^ user.cpp: In function ‘int main()’: user.cpp:41:24: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%d",&t); ^ user.cpp:44:37: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%lld%lld",&a,&b); ^