Given a number N find how many integers from 1 to N contains 0's as a digit.

Example 1:
Input: N = 20
Output: 2
Explanation: 10 and 20 has '0' as a digit.
Example 2:
Input: N = 100
Output: 10
Explanation: 10, 20, 30, 40, 50, 60, 70,
80, 90, 100 has '0' as a digit.

Your Task:
You don't need to read or print anything. Your task is to complete the function CountNo() which takes N as input parameter and returns the count of numbers which contains '0' as a digit.

Expected Time Complexity: O(N * log_{10}(N))
Expected Space Complexity: O(1)

Constraints:
1 <= N <= 10000

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