Given a Binary tree and a number N, write a program to find the N-th node in the Postorder traversal of the given Binary tree.
Prerequisite: Tree Traversal
Input : N = 4 11 / \ 21 31 / \ 41 51 Output : 31 Explanation: Postorder Traversal of given Binary Tree is 41 51 21 31 11, so 4th node will be 31. Input : N = 5 25 / \ 20 30 / \ / \ 18 22 24 32 Output : 32
The idea to solve this problem is to do postorder traversal of the given binary tree and keep track of the count of nodes visited while traversing the tree and print the current node when the count becomes equal to N.
Below is the implementation of the above approach:
Time Complexity: O(n), where n is the number of nodes in the given binary tree.
Auxiliary Space: O(1)
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