Boom numbers are numbers consisting only of digits 2 and 3. Given an integer K, display the K-th Boom number.
Example 1:
Input:
K = 5
Output: 32
Explanation:
The Boom series is 2, 3, 22, 23, 32, 33, 222....
and, for K=5, answer = 32

Example 2:
Input:
K = 100
Output: 322323
Your Task:
You don't need to read input or print anything. Your task is to complete the function BoomNumber() which takes an interger K as input parameter and returns the K^{th} boom number in the form of a string.

Expected Time Complexity: O( log(K) )
Expected Auxiliary Space: O( log(K) )
Constraints:
1 ≤ K ≤ 10^{12}

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