Can't build full bst from the preorder array

#1

I am trying to build bst from preorder traversal in this code but only the left subtree is getting built.Can you please help me understand my mistake?

#2

@Sayon-Palit-2873308702757758 can you share the approach you are using to build the tree? There is a video in the course covering how to build a BST from an array, you can refer to that also.

#3

That video just says to find your own solution

#4

My approach is to iterate over the array , in the beginning just insert element as root ,next the left node must be b/w INT_MIN and the root , and right will be between root and INT_MAX and recursively build the tree using this

#5

hi @Sayon-Palit-2873308702757758 look for it in the concepts there must be a video explaining how to build a BST.
The approach is to, iterate over the array and insert each element individually.
For insertion, if root is NULL, make a node and return that node.
else, if the element is smaller or equal to the root node, insert in left part or else insert it in the right part.

#6

yes that is the soln for a normal array but since this is preorder it may become a skewed tree in cases like 1 2 3 4 …

#7

@Sayon-Palit-2873308702757758 where does it say that pre-order traversal is given?

#8

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