Problem Statement

Given   M   as a list of items and another list   N   of items chosen from   M,   create   M'   as a list with the first occurrences of items from   N   sorted to be in one of the set of indices of their original occurrence in   M   but in the order given by their order in   N. That is, items in   N   are taken from   M   without replacement, then the corresponding positions in   M'   are filled by successive items from   N.

The words not in   N   are left in their original positions.

If there are duplications then only the first instances in   M   up to as many as are mentioned in   N   are potentially re-ordered.

Is ordered as:

Show the output, here, for at least the following inputs:

Let's start with the solution: