## Number of Digit One

https://leetcode.com/problems/number-of-digit-one/ Given an integer n, count the total number of digit 1 appearing in all non-negative integers less than or equal to n. For example: Given n = 13, Return 6, because digit 1 occurred in the following numbers: 1, 10, 11, 12, 13. Solution. The solution is to iterate each digit. Each time, split… Read More »