Longest Common Subsequence
Detailed guide and Python implementation for the 'Longest Common Subsequence' problem.
Problem Statement
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").
Write a function longestCommonSubsequence(text1: str, text2: str) -> int.
- •1 <= len(text1), len(text2) <= 1000
- •text1 and text2 consist of only lowercase English characters
Examples
text1 = "abcde", text2 = "ace"
3
The longest common subsequence is "ace" and its length is 3.
text1 = "abc", text2 = "abc"
3
The longest common subsequence is "abc" and its length is 3.
text1 = "abc", text2 = "def"
0
There is no common subsequence, so the result is 0.
Need a Hint?
Edge Cases to Watch
- Empty input structures
- Single element inputs
- Large numerical bounds
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