int_sorted::int_sorted(const int *source, size_t size):sint_buffer(source, size){
    if (!check_sorted(sint_buffer)){ // return if already sorted
        int_buffer tmp(source, size);
        for (int *i = sint_buffer.begin(); i != sint_buffer.end(); i++) // loop through int_buffer
            insert(*i); // insert into to-be sorted buffer
        sint_buffer = tmp;
    }
}