Given a positive integer X. The task is to find the smallest even number E such that
E > X and all digits in X and E are the same.
Note: All the digits in X should be same with digits in E.

Example 1:
Input:
X = 34722641
Output:
34724126
Explanation:
Next greater number with same
digits as in input is 34724126.
Example 2:
Input:
X = 111
Output:
-1
Explanation:
You can't rearrange the digits to get an answer.

Your Task:
You don't need to read input or print anything. Your task is to complete the function getNextEven() which takes a string X as input, which is representing the number and returns the required smallest even number. If no such even number exists return -1.
Expected Time Complexity: O(Log(N)! )
Expected Auxiliary Space: O(Log(N))
Constraints:
1 ≤ N ≤ 10^{9}

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