**Longest Common Subsequence** ================================ **Problem Statement** ------------------- Given two strings `X` and `Y`, find the length of their **Longest Common Subsequence (LCS)**. A **Longest Common Subsequence** is a sequence that appears in the same order in both `X` and `Y` and has no common elements other than those from `X` and `Y`. This means that the sequence should not be a subset of another string within `X` or `Y`. **Rules and Constraints** ------------------------- * The input strings `X` and `Y` are of arbitrary length and comprise alphanumeric characters only. * The output is an integer representing the length of the Longest Common Subsequence. * Time and space complexity constraints: * Time complexity: O(m*n) where `m` and `n` are the lengths of `X` and `Y`, respectively. This is because we will be using a 2D array to store the dynamic programming table, and we need to iterate over each character in both strings once. * Space complexity: O(m*n) to store the dynamic programming table. **Requirements** --------------- Your solution should be written in a programming language supported by our platform. It should be a standalone function that takes two string parameters, `X` and `Y`, and returns an integer representing the length of the Longest Common Subsequence. ### Example **Input:** {"input_data":[1,2,3]} **Output:** [1,2,3]