Dsa
Math
Medium
Numerical Pattern Count
You are tasked with counting how many times a given digit appears in the numbers from 1 to N, inclusive.
Input:
A single integer N (1 <= N <= 10^6).
Output:
An integer representing the total count of the digit '3' in all numbers from 1 to N.
Example:
Input:
30
Output:
13
Explanation: The digit '3' appears in the numbers: 3, 13, 23, 30 (total of 4 occurrences).
Key concepts
mathpatterncount
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