Finding Nth Digit is an example of math problems. In this post we will see how we can solve it in Javascript.

Problem Description

Find the n-th digit of the infinite integer sequence 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, ...

Note: n is positive and will fit within the range of a 32-bit signed integer (n < 231).

Example 1:

Input: 3
Output: 3

Example 2:

Input: 11
Output: 0

Explanation: The 11th 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.

Solution

  • Straight forward way to solve the problem in 3 steps:
  • Find the length of the number where the nth digit is from
  • Find the actual number where the nth digit is from
  • Find the nth digit and return 

Implementation: Please check the main.js snippet for the solution. If you have different approach in mind or have any suggestion for this implementation feel free to share in the comment below. Thanks!

Originally posted at: @github.com/jeantimex/javascript-problems-and-solutions