Question 5
Five birds are queuing to go to nests in a tree (see the illustration). The birds are distinguished by the number of spots on their heads.
On its turn, each bird starts at the root and follows these instructions:
- Go upward until reaching a nest.
- If the nest is empty, enter it and stay there.
- If another bird is already there, choose a branch and continue:
- If you have fewer spots than that bird, go left.
- Otherwise, go right.
With this ordering, which bird will live in the highest nest?
On its turn, each bird starts at the root and follows these instructions:
- Go upward until reaching a nest.
- If the nest is empty, enter it and stay there.
- If another bird is already there, choose a branch and continue:
- If you have fewer spots than that bird, go left.
- Otherwise, go right.
With this ordering, which bird will live in the highest nest?
