Number of Digits in Java

Given a non-negative integer n, return how many digits it has.

The digits are the figures from 0 to 9 that n is written with. Dividing a number by 10 without the remainder removes its last digit (542 becomes 54), so you can count how many times that happens until the number is 0. The number 0 itself has one digit.

Example 1:

Input: n = 542
Output: 3
Explanation: 542 is written with three digits: 5, 4 and 2.

Example 2:

Input: n = 100
Output: 3
Explanation: The zeros are digits too: 1, 0 and 0.

Example 3:

Input: n = 0
Output: 1
Explanation: 0 is written with one digit.

Constraints:

• 0 <= n <= 109