Given a BST and a number X, find Ceil of X.
Note: Ceil(X) is a number that is either equal to X or is immediately greater than X.
Example 1:
Input:
5
/ \
1 7
\
2
\
3
X = 3
Output: 3
Explanation: We find 3 in BST, so ceil
of 3 is 3.
Example 2:
Input:
10
/ \
5 11
/ \
4 7
\
8
X = 6
Output: 7
Explanation: We find 7 in BST, so ceil
of 6 is 7.
Your task:
You don't need to read input or print anything. Just complete the function findCeil() to implement ceil in BST which returns the ceil of X in the given BST.
Expected Time Complexity: O(Height of the BST)
Expected Auxiliary Space: O(Height of the BST).
Constraints:
1 <= Number of nodes <= 10^{5}
1 <= Value of nodes<= 10^{5}

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