Given a value N, find out the largest palindrome number which is product of two N-digit numbers.

Example 1:
Input: N = 2
Output: 9009
Explanation: 9009 is the largest number
which is product of two 2-digit numbers.
9009 = 91*99.
Example 2:
Input: N = 1
Output: 9
Explanation: 9 is the largest number
which is product of two 1-digit numbers.
3 * 3 = 9.

Your Task:
You don't need to read or print anyhting. Your task is to complete the function LargestProductPalin() which takes N as input parameter and returns largest palindromic product of 2 N-digit numbers.

Expected Time Complexity: O(10^{n+1})
Expected Space Complexity: O(1)

Constraints:
1 <= N <= 6

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