Given two numbers in the form of Strings. Find the count of carries in their addition.

Example 1:
Input:
N = "34", M = "25"
Output:
0
Explanation:
There are no carries when N and M
are added.
Example 2:
Input:
N = "4634", M = "1757"
Output:
2
Explanation:
There are 2 carries when N and M
are added.

Your Task:
You don't need to read input or print anything. Your task is to complete the function getCarries() which takes two Strings N and M as input and returns an integer denoting the answer.

Expected Time Complexity: O(|N|)
Expected Auxiliary Space: O(|N|)

Constraints:
1 <= |N|,|M| <= 10^{5}

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