# When do i say that a binary search tree is unique?!

Nadine Ernest

Greenhorn

Posts: 27

posted 7 years ago

Hi,

given the following:

90,50,20,5,25,75,66,80,150,95,92,111,175,166,200.

i constructed the binary tree and the traversal was preorder traversal : root, left, right

and then Is the tree unique?!

yes , the tree is unique,

i dont understand why?!

given the following:

90,50,20,5,25,75,66,80,150,95,92,111,175,166,200.

i constructed the binary tree and the traversal was preorder traversal : root, left, right

and then Is the tree unique?!

yes , the tree is unique,

i dont understand why?!

What Doesn't Kill You, Makes You Stronger!

Piet Verdriet

Ranch Hand

Posts: 266

posted 7 years ago

Because it's a binary search tree. With a regular binary tree, the order of the elements doesn't matter, so the pre-order traversal of [3,2,4] could be:

But with a binary

Nadine Ernest wrote:Hi,

given the following:

90,50,20,5,25,75,66,80,150,95,92,111,175,166,200.

i constructed the binary tree and the traversal was preorder traversal : root, left, right

and then Is the tree unique?!

yes , the tree is unique,

i dont understand why?!

Because it's a binary search tree. With a regular binary tree, the order of the elements doesn't matter, so the pre-order traversal of [3,2,4] could be:

But with a binary

*search*tree, you start with 3, and the insert 2 to the left (because it's less than 3) and insert 4 into the right (because it's more than 3), resulting in:

Campbell Ritchie

Sheriff

Posts: 48652

56

Nadine Ernest

Greenhorn

Posts: 27

posted 7 years ago

Hi campbell ritchie, i actually asked the question to a friend of mine!

she told me that the tree is unique meaning that with the preorder and inorder traversal the tree has JUST ONE SHAPE!!

not many!

thanks guys for your help!!

so actually yeah when you draw this tree it is unique!!

she told me that the tree is unique meaning that with the preorder and inorder traversal the tree has JUST ONE SHAPE!!

not many!

thanks guys for your help!!

so actually yeah when you draw this tree it is unique!!

What Doesn't Kill You, Makes You Stronger!