How do you solve Generate Binary Strings Without Adjacent Zeros on LeetCode?

Generate Binary Strings Without Adjacent Zeros (LeetCode #3211) can be solved using Brute Force or Optimal Solution. The optimal approach is Optimal Solution with O(n) time complexity and O(n) space complexity. Key insight: Adjacent zeros are the only invalid condition.

What is the time complexity of Generate Binary Strings Without Adjacent Zeros?

The optimal solution for Generate Binary Strings Without Adjacent Zeros runs in O(n) time and uses O(n) space. Each valid string is built directly, leading to linear time complexity relative to the number of valid strings.

What is the brute force solution for Generate Binary Strings Without Adjacent Zeros?

The brute force approach for Generate Binary Strings Without Adjacent Zeros is Brute Force, with O(n²) time complexity and O(1) space complexity. Generate all possible binary strings of length n and filter out invalid ones. This approach is straightforward but inefficient. The optimal Optimal Solution approach improves this to O(n).

What algorithm or data structure is used to solve Generate Binary Strings Without Adjacent Zeros?

Generate Binary Strings Without Adjacent Zeros uses the following concepts: String, Backtracking, Bit Manipulation. The recommended patterns to study are: Backtracking, Dynamic Programming.

What are the interview tips for Generate Binary Strings Without Adjacent Zeros?

Explain your thought process clearly. Consider edge cases like n = 1. Discuss time and space complexity.

What are common mistakes when solving Generate Binary Strings Without Adjacent Zeros?

Generating all combinations instead of filtering during generation. Not handling the last character condition correctly.

#3211

Generate Binary Strings Without Adjacent Zeros

Medium

StringBacktrackingBit ManipulationBacktrackingDynamic Programming

LeetCode ↗

Approaches

Brute ForceOptimal

Complexity Comparison

	Brute Force	Optimal Solution★
Time	O(n²)	O(n)
Space	O(1)	O(n)

💡

Intuition

Time O(n)Space O(n)

Use backtracking to build valid strings directly, avoiding invalid combinations from the start.

⚙️

Algorithm

3 steps

1Step 1: Start with an empty string and recursively add '0' or '1'.
2Step 2: If the last character is '0', only add '1'. If it's '1', add both '0' and '1'.
3Step 3: Stop when the string reaches length n and add it to the result.

solution.py11 lines

1def generateBinaryStrings(n):
2    result = []
3    def backtrack(s):
4        if len(s) == n:
5            result.append(s)
6            return
7        backtrack(s + '1')
8        if not s or s[-1] == '1':
9            backtrack(s + '0')
10    backtrack('')
11    return result

ℹ

Complexity note: Each valid string is built directly, leading to linear time complexity relative to the number of valid strings.

1Adjacent zeros are the only invalid condition.
2Backtracking allows for efficient string generation.

Solutions and explanations are original Tejav content. Problem titles © LeetCode — use the LeetCode button above for the full problem statement.