Simulation preorder

Simulation preorder is like playing with blocks. Imagine you have a bunch of different-shaped blocks, and you want to see if you can put all the little blocks inside one big block without any of them sticking out.

The simulation preorder is a way of checking if you can do that by imagining what will happen if you try to fit different blocks together.

To make it easier, you start with smaller groups of blocks and see if they can fit inside each other. If they can, you move on to larger groups until you get to the big block.

This way you can see which blocks can fit inside each other and make a plan to put them all together without any sticking out.

It's like a puzzle, where you have to think about all the different ways things could fit together and figure out the best way to make it all work.