Longest Palindromic Subsequence
Detailed guide and Python implementation for the 'Longest Palindromic Subsequence' problem.
Problem Statement
Write a function lps(s) that finds the length of the longest palindromic subsequence in a string s. A subsequence is a sequence that can be derived from another sequence by deleting some or no elements without changing the order of the remaining elements.
- •1 <= len(s) <= 1000
- •s consists of uppercase or lowercase English letters.
Examples
lps('BBABCBCAB')7
The longest palindromic subsequence has length 7, e.g., 'BABCBAB'.
lps('GEEKSFORGEEKS')5
The longest palindromic subsequence has length 5, e.g., 'EEKEE'.
Need a Hint?
Edge Cases to Watch
- Empty input structures
- Single element inputs
- Large numerical bounds
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