Given a Binary tree, the problem is to find mirror of a given node. The mirror of a node is a node which exist at the mirror position of node in opposite subtree at the root.
Example 1:
Input:
1
/ \
2 3
/ \ / \
4 5 6 7
and target = 4
Output: 7
Explanation: You can see below that the mirror
node of 4 is 7.
1 | 1
/ \ | / \
2 3 | 3 2
/ \ / \ | / \ / \
4 5 6 7 | 7 6 5 4
Example 2:
Input:
1
/ \
2 3
/ \
4 5
and target = 4
Output: -1
Your Task:
You don't need to read input or print anything. Your task is to complete the function findMirror() which takes root node of the tree and a integer target as input parameter and returns the value of the mirror node of the given target node. If the mirror node does not exists return -1.
Expected Time Complexity: O(N)
Expected Auxiliary Space: O(N)
Constraints:
1<=n<=10^{4}
1<=data of node<=10^{4}
1<=target<=10^{4}

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