Chapter 8, Problem 18SE

In Exercises 15-18 we develop a dynamic programming algorithm for finding a longest common subsequence of two sequences $a_1,a_2,\mathrm{....},a_m$ and $b_1,b_2,\mathrm{....},b_n$, an important problem in the comparison of DNA of different organisms.

Develop an algorithm for finding a longest common subsequence of two sequences $a_1,a_2,\mathrm{....},a_m$ and $b_1,b_2,\mathrm{....},b_n$ using the values L(i,j) found by the algorithm in Exercise 17.