A Visual Guide to Longest Common Subsequence Another type of problem that arises in computer science is finding the longest common subsequence. If you have the following string, BEADCA and ABCDA, what is the longest common subsequence? You can probably quickly figure out that the longest common subsequence of these two strings is BDA. It is possible to have multiple subsequences that are of equal length that would work. Let’s see how we would find the longest common subsequence in this problem. We begin by constructing a matrix. One sequence goes on top of the matrix and the other goes