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How to Solve Longest Palindrome by Concatenating Two Letter Words Problem
Master the Longest Palindrome by Concatenating Two Letter Words LeetCode problem with undetectable real-time assistance. Get instant solutions and explanations during your coding interviews.
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Start Free for WindowsMedium#2131
LeetCode ProblemLongest Palindrome by Concatenating Two Letter Words
You are given an array of strings words. Each element of words consists of two lowercase English letters. Create the longest possible palindrome by selecting some elements from words and concatenating them in any order. Each element can be selected at most once. Return the length of the longest palindrome that you can create. If it is impossible to create any palindrome, return 0. A palindrome is a string that reads the same forward and backward.
ArrayHash TableStringGreedyCounting
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Problem Breakdown
Understanding the Longest Palindrome by Concatenating Two Letter Words Problem
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Problem Statement
You are given an array of strings words. Each element of words consists of two lowercase English letters. Create the longest possible palindrome by selecting some elements from words and concatenating them in any order. Each element can be selected at most once. Return the length of the longest palindrome that you can create. If it is impossible to create any palindrome, return 0. A palindrome is a string that reads the same forward and backward.
MediumProblem #2131
LeetCodeLongest Palindrome by Concatenating Two Letter Words
Related Topics
ArrayHash TableStringGreedyCounting
How Phantom Code Helps
Get real-time assistance for Longest Palindrome by Concatenating Two Letter Words problems during coding interviews. Phantom Code provides instant solutions and explanations.
Examples
# Example 1
Input
words = ["lc","cl","gg"]
Output
6
# Example 2
Input
words = ["ab","ty","yt","lc","cl","ab"]
Output
8
# Example 3
Input
words = ["cc","ll","xx"]
Output
2
Constraints
1 <= words.length <= 105
words[i].length == 2
words[i] consists of lowercase English letters.
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Solve Longest Palindrome by Concatenating Two Letter Words — You are given an array of strings words. Each element of words consists of two l...
Here's the optimal approach using Array:
def solve(input):
# Optimal O(n) solution
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Time: O(n) | Space: O(n)
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Frequently Asked Questions
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Phantom Code generates complete solutions instantly with proper complexity analysis, letting you focus on explaining your approach and demonstrating problem-solving skills rather than getting stuck on implementation details during high-pressure situations.
What if the interviewer asks follow-up questions or modifications to problems like Longest Palindrome by Concatenating Two Letter Words?
Phantom Code adapts in real-time. Screenshot the modified problem or use audio mode to capture the interviewer's follow-up, and get an updated solution within seconds — including edge cases and optimizations.
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Yes. Phantom Code provides step-by-step approach explanations with 3 progressive thoughts, so you can walk through your solution naturally. It also provides time and space complexity analysis to discuss trade-offs.
How does Phantom Code assist with different programming languages for Longest Palindrome by Concatenating Two Letter Words type problems?
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What coding mistakes does Phantom Code help me avoid during Longest Palindrome by Concatenating Two Letter Words interviews?
Phantom Code catches common mistakes like off-by-one errors, missing edge cases, incorrect base conditions, and suboptimal approaches. It provides clean, well-structured code that handles all edge cases.
Is Phantom Code detectable when solving problems like Longest Palindrome by Concatenating Two Letter Words during live interviews?
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How does Phantom Code help when I'm struggling with Longest Palindrome by Concatenating Two Letter Words style questions under pressure?
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Does Phantom Code work for the coding platforms used in Longest Palindrome by Concatenating Two Letter Words interviews?
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