1215. Stepping Numbers

https://leetcode.com/problems/stepping-numbers

Description

A stepping number is an integer such that all of its adjacent digits have an absolute difference of exactly 1.

• For example, 321 is a stepping number while 421 is not.

Given two integers low and high, return a sorted list of all the stepping numbers in the inclusive range [low, high].

Example 1:

**Input:** low = 0, high = 21
**Output:** [0,1,2,3,4,5,6,7,8,9,10,12,21]

Example 2:

**Input:** low = 10, high = 15
**Output:** [10,12]

Constraints:

• 0 <= low <= high <= 2 * 109

ac