Given a binary tree and an integer value K, the task is to find all nodes data in the given binary tree having exactly K leaves in sub-tree rooted with them.
NOTE: Nodes should be printed in the order in which they appear in postorder traversal.
Example 1:
Input:
K = 1
0
/ \
1 2
Output: -1
Explanation: There is no node in this
tree which has one leaf in the sub tree
below it.
Example 2:
Input:
K = 2
0
/ \
1 2
/
4
/ \
5 9
Output: 4 2
Explanation: Nodes with data 2 and 4, have
2 leaves in the subtree below it.
Your Task:
Just complete the function btWithKleaves() and returns the answer (as a vector in CPP, as an ArrayList in java, and as list in python)
Note: If no node is found the list returned should contain only one value -1.
Expected Time Complexity: O(N).
Expected Auxiliary Space: O(Height of the Tree).
Constraints:
1 <= N <= 1000
1 <= K <= 1000
1 <= value of nodes <= 10000

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