Longest Common Subsequence

Given two strings `text1` and `text2`, return _the length of their longest **common subsequence**. _If there is no **common subsequence**, return `0`. A **subsequence** of a string is a new string generated from the original string with some characters (can be none) deleted without changing the relative order of the remaining characters. - For example, `"ace"` is a subsequence of `"abcde"`. A **common subsequence** of two strings is a subsequence that is common to both strings.   **Example 1:** **Input:** text1 = "abcde", text2 = "ace" **Output:** 3 **Explanation:** The longest common subsequence is "ace" and its length is 3. ``` **Example 2:** **Input:** text1 = "abc", text2 = "abc" **Output:** 3 **Explanation:** The longest common subsequence is "abc" and its length is 3. ``` **Example 3:** **Input:** text1 = "abc", text2 = "def" **Output:** 0 **Explanation:** There is no such common subsequence, so the result is 0. ```   **Constraints:** - `1 <= text1.length, text2.length <= 1000` - `text1` and `text2` consist of only lowercase English characters.