Solution: Longest Common Subsequence
Explore how to solve the longest common subsequence problem using a dynamic programming approach. Understand how memoization and a 2D table optimize the recursive solution, reducing time complexity from exponential to polynomial. This lesson helps you implement and analyze an efficient algorithm for this classic coding interview problem.
Statement
Suppose you are given two strings. You need to find the length of the longest common subsequence between these two strings.
A subsequence is a string formed by removing some characters from the original string while maintaining the relative position of the remaining characters. For example, “abd” is a subsequence of “abcd”, where the removed character is “c”.
If there is no common subsequence, then return 0.
Constraints:
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str1.length