Geek wants to know the traversals required to construct a unique binary tree. Given a pair of traversal, return true if it is possible to construct unique binary tree from the given traversals otherwise return false.
Each traversal is represented with an integer: preorder - 1, inorder - 2, postorder - 3.
Example 1:
Input:
a = 1, b=2
Output: 1
Explanation: We can construct binary tree using inorder traversal and preorder traversal.
Example 2:
Input: a = 1, b=3
Output: 0
Explanation: We cannot construct binary tree using preorder traversal and postorder traversal.
Constraints:
1 <= a,b <=3
Your Task:
You don't need to read input or print anything. Your task is to complete the function isPossible() which takes a and b as input parameters and returns true or false.
Expected Time Complexity: O(1)
Expected Auxiliary Space: O(1)

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