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Codeforces
Easy
Strings
Arrays
Sorting
Lecture

Reorder a sequence of lecture topics so that they appear in the same order as an official reference list.

Acceptance 0%
Problem Statement

You are given a list of lecture topic names and another list that describes the desired order of those topics. Reorder the first list so that the topics appear in the order specified by the second list.

Each topic from the first list will appear exactly once in the reference order list, so the task is to map each topic to its position in the order list and sort accordingly. The relative order of topics not covered by the reference list is not relevant in this problem setup.

Input Format

  • The input describes two ordered collections of strings.
  • The first collection contains the lecture topics to be reordered.
  • The second collection contains the reference order of all topics.
  • Topic names are case-sensitive.

Output Format

  • Output the lecture topics in the reordered sequence.
  • Preserve the exact topic names from the input.

Constraints

  • The number of topics is small to moderate.
  • All lecture topics are assumed to be present in the reference order list.
  • Topic names are unique within each collection.
Examples
Sample cases returned by the problem API.

Example 1

Input

topics = ["math", "algorithms", "dp"]
order = ["dp", "math", "algorithms"]

Output

["dp", "math", "algorithms"]

Explanation

Each topic is assigned its index in the reference order: dp -> 0, math -> 1, algorithms -> 2. Sorting by those indices gives the required sequence.

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