Given preorder traversal of a binary tree, check if it is possible that it is also a preorder traversal of a BST,
where each internal node (non -leaf nodes) have exactly one child.
CONSTRAINTS
1 <= N <= 100
INPUT
A : [ 4, 10, 5 ,8 ]
OUTPUT
YES
EXPLANATION
The possible BST is:
4
\
10
/
5
\
8
NOTE: You only need to implement the given function. Do not read input, instead use the arguments to the function. Do not print the output, instead return values as specified. Still have a doubt? Checkout Sample Codes for more details.