Given two integers A and B. Find the smallest number X (greater than A) which is divisible by B.

Example 1:
Input:
A = 5
B = 3
Output:
6
Explanation:
6 is the smallest number
greater than 5 which is
divisible by 3
Example 2:
Input:
A = 25
B = 13
Output:
26
Explanation:
26 is the smallest number
greater than 25 which is
divisible by 13
Your Task:
You don't need to read input or print anything. Your task is to complete the function find() which takes two integers A and B as input parameters and returns a smallest possible integer greater than A which is divisible by B.

Expected Time Complexity: O(1)
Expected Space Complexity: O(1)

Constraints:
0 <= A,B <= 10^{9}

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