Given a range [m..n]. You task is to find the number of integers divisible by either a or b in the given range.

Example 1:
Input:
m = 5, n = 11, a = 4, b = 6
Output:
2
Explanation:
6 and 8 lie in the range and are also
either divisible by 4 or 6.
Example 2:
Input:
m = 1, n = 3, a = 2, b = 3
Output:
2
Explanation:
2 and 3 lie in the range and are also
either divisible by 2 or 3.

Your Task:
You don't need to read input or print anything. Your task is to complete the function numOfDiv() which takes 4 Integers m, n, a, b as input and returns the count of integers in the range m..n which are divisible by either a or b.

Expected Time Complexity: O(log(max(a,b))
Expected Auxiliary Space: O(1)

Constraints:
1 <= m <= n <= 10^{5}
1 <= a,b <= 500

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