Search mehtods applied to the edit distance problem.
The problem of calculating the edit distance between two strings
is to find the minimum number of operations that are required in order
to change one string into the other where the operations are
substitution, insertion, and deletion (single letter).
This can be formulated as a graph problem, where the edit distance
corresponds to the shortest path from the start node S
to the goal node Gin a weighted graph, the edit graph.
Draw the edit graph for the strings AC and AT.
The dynamic programming principle according to Winston can now
be applied to the search for the shortest path in the edit graph.
Discuss how this is similar to the standard dynamic programming
algorithm for sequence alignment.
Can the A* algorithm be used to find the edit distance?
If so, would it be faster than the standard dynamic programming
algorithm to calculate the edit distance between two strings?
If we use similarity scoring instead of distance, the problem becomes
finding the longest path in the graph. How will this affect
the search problem, especially the A* algorithm?