Given two integers L and R . Find the resultant after applying the series of Bitwise AND ( & ) operation on every natural number between the Range L and R (including both).

Example 1:
Input: L = 8, R = 13
Output: 8
Explanation:
8 AND 9 AND 10 AND 11 AND 12 AND 13 = 8.
Example 2:
Input: L = 2, R = 3
Output: 2
Explanation: 2 AND 3 = 2.

Your Task:
You don't need to read or print anything. Your task is to complete the function find_and() which takes l and r as input parameter and returns AND operation on every number between l to r.

Expected Time Complexity: O(log(n))
Expected Time Complexity: O(1)

Constraints:
1 <= L<= R < =10^{8}

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