Transpose Heuristic

Problem

Compute the total cost of transpose-heuristic accesses on a list.

items is the initial list order and accesses is the sequence of requested items, all present in items. Each access costs the item's current 1-based position, and when the item is not first it swaps with the preceding element.

Return the total access cost.

Hint

A requested item moves only one step toward the front.

Test cases

case 1

in: [[1,2,3],[3,2,3]]

expected: 9

case 2

in: [[1,2,3],[1,2,3]]

expected: 6

case 3

in: [[1,2],[2,2]]

expected: 3

case 4

in: [[1,2,3,4],[4,4,3,2]]

expected: 15

Starter codePython

def transpose_cost(items, accesses):
    # Your code here
    pass

4 test cases · run your code against them in the editor