3211: Generate Binary Strings Without Adjacent Zeros

Problem Statement

You are given a positive integer n.

A binary string x is valid if all substrings of x of length 2 contain at least one "1".

Return all valid strings with length n, in any order.

Example 1:

Input: n = 3

Output: ["010","011","101","110","111"]

Explanation:

The valid strings of length 3 are: "010", "011", "101", "110", and "111".

Example 2:

Input: n = 1

Output: ["0","1"]

Explanation:

The valid strings of length 1 are: "0" and "1".

Constraints:

  • 1 <= n <= 18

Code Solution