Given two numbers X and N, find the smallest value of (N*K) which is closest to X. Where K is any positive number greater than zero. If in case there are two numbers closer to N, then return the larger number.

Example 1:
Input: X = 9, N = 2
Output: 10
Expalantion: 8 and 10 both are multiple of 2 and
closest to 9, in this case we return the larger
number that is 10.
Example 2:
Input: X = 2855, N = 13
Output: 2860
Explanation: 2860 is multiple of 13 and
closest to 13.

Your Task:
You don't need to read or print anything. Your task is to complete the function closestNo() which takes X and N as input parameter and return the number which is multiple of N and closest to X. In case of multiple numbers return the bigger one.
Expected Time Compelxity: O(1)
Expected Space Complexity: O(1)
Constraints:
1 <= X, N <= 1000000

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