Is Palindrome Partitioning easy or hard?

Palindrome Partitioning is generally classified as a medium-level problem. The basic backtracking idea is straightforward, but handling recursion correctly and optimizing palindrome checks with dynamic programming makes it a solid interview challenge.

Palindrome Partitioning Python/Java solution

Python and Java implementations typically use recursive backtracking to explore partitions. Each recursive call expands the substring boundary and verifies whether the segment is a palindrome. Optimized versions add a DP table to cache palindrome results so each substring check runs in O(1).

How to solve Palindrome Partitioning in O(n)?

Generating all palindrome partitions cannot be solved in O(n) because the output itself can contain up to 2^n combinations. The best achievable approach is O(n * 2^n) using backtracking with a dynamic programming table that precomputes palindrome substrings in O(n^2).

What is the best approach for Palindrome Partitioning?

Backtracking combined with dynamic programming for palindrome checks is the most efficient practical approach. Precompute a DP table where dp[i][j] indicates whether substring s[i..j] is a palindrome, then run recursive backtracking to build partitions. This avoids repeated substring scans and reduces constant overhead while exploring the partition space.

Is Palindrome Partitioning asked at Google/Amazon/Meta?

Palindrome Partitioning is a common interview problem at large tech companies including Amazon, Google, and Meta. It tests backtracking, recursion design, and optimization with dynamic programming, making it a frequent medium-level string problem in technical interviews.

What data structure is used in Palindrome Partitioning?

The solution primarily uses recursion with a dynamic list to store the current partition path. Many optimized implementations also use a 2D boolean DP table to store palindrome results for substrings, enabling constant-time checks during backtracking.

What is the time complexity of Palindrome Partitioning?

The overall time complexity is O(n * 2^n). A string of length n can produce up to 2^n possible partitions in the worst case, and each partition construction may involve up to O(n) work. With DP precomputation, palindrome validation becomes O(1), but the exponential number of partitions remains the dominant factor.

Description Solution Video 24:34

131. Palindrome Partitioning

Medium74.4% acceptance10 companies

Given a string s, partition s such that every substring of the partition is a palindrome. Return all possible palindrome partitioning of s.

Example 1:

Input: s = "aab"
Output: [["a","a","b"],["aa","b"]]

Example 2:

Input: s = "a"
Output: [["a"]]

Constraints:

1 <= s.length <= 16
s contains only lowercase English letters.

Asked at 10 companies

Scaler Bloomberg

Infosys Visa Coupang

Google Amazon Microsoft Meta Accenture

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131. Palindrome Partitioning

Asked at 10 companies

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