400\. Nth Digit

Medium

Given an integer `n`, return the <code>n<sup>th</sup></code> digit of the infinite integer sequence `[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, ...]`.

**Example 1:**

**Input:** n = 3

**Output:** 3 

**Example 2:**

**Input:** n = 11

**Output:** 0

**Explanation:** The 11<sup>th</sup> digit of the sequence 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, ... is a 0, which is part of the number 10. 

**Constraints:**

*   <code>1 <= n <= 2<sup>31</sup> - 1</code>