I did this once when I was about 12 years old.
I’d like to say it took some concentrated effort but alas, it did not. I sat down with it for about an hour and before I knew it, it was done.
I have never been able to sit with it long enough to solve it a second time. It feels tedious and irritating. But I can not tell a lie… I have a small feeling of accomplishment, somewhere deep in my spirit. :I