Given two strings a1a2an and b1b2bm, find their minimum edit distance. The edit distance is the number of mismatches in an alignment. For example, the minimum edit distance between the two strings "SUNNY" and "SNOWY" in the following alignment is 3 : Likewise, the minimum edit distance between "INTENTION" and "EXECUTION" is 5. (a) Represent the minimum edit distance between a1a2ak and b1b2bl by a function name. (b) Every function has variable(s). Now, it is time to decide on them, by which you can narrow down the problem into sub-problems. This is usually straightforward, since the function's variables mostly correspond to the problem's input variable(s) or indices that make it easier to construct smaller sub-problems. For example, the matrix indices in the Matrix chain Multiplication, the index of the last item we consider and the weight capacity in the Knapsack, or the lengths of the two sequences in Longest Common Subsequence etc. However, there are no variables related to the three possible weights (i.e. 1,4,5) but only the weight capacity in the unbounded Knapsack because the weights are constants given to the problem. Write down the variables of your function in between parenthesis and define what your function represents as complete and concise as possible in only one sentence, as we did in class (e.g. Given a string Xi of length i and another string Yj of length j, c(i,j) represents the length of their longest common subsequence in the longest Common Subsequence problem.)