Longest Palindromic Subsequence Problem Statement

Given a string A consisting of lowercase English letters, determine the length of the longest palindromic subsequence within A.

Explanation:

  • A subsequence is derived from a string by deleting some or no characters without changing the order of the remaining characters.
  • A string is a palindrome if it reads the same forwards and backwards (e.g., "abba").

Input:

The first line contains an integer ‘T’, indicating the number of test cases. Each test case consists of a single string ‘A’.

Output:

Output a single integer per test case, representing the length of the longest palindromic subsequence in ‘A’.

Example:

Input: 
2
bbabcbcab
dcbccbcabbb

Output:
7
7

Constraints:

  • 1 <= T <= 10
  • 1 <= N <= 102
  • Where ‘T’ represents the number of test cases and ‘N’ represents the length of the string.
  • Time limit: 1 second.

Note:

No need to print anything; implement the function to obtain the result.
AnswerBot
4mo

Find the length of the longest palindromic subsequence in a given string.

  • Use dynamic programming to solve this problem efficiently.

  • Create a 2D array to store the lengths of palindromic subsequences fo...read more

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