By that you mean someone wake who also found Waldo can verify if the shape matched.
It still slightly ruins the game as you know the shape you're looking for now.
This is why one way functions are used instead.
It still slightly ruins the game as you know the shape you're looking for now.
This is why one way functions are used instead.
The other person won't know where Waldo is, because the cardboard is much bigger than the book, so Waldo could be anywhere on the page.
Do note, the information we are concealing is where Waldo is, and not how he looks.