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📜 WAYPOINT LESSON

Checkpoint — Collections

⭐ beginner⏳ 20 min read📍 Lesson 33 of 85

A gradebook: per-student averages, a class ranking, and honors detection — Dictionary, List, and a little LINQ-free aggregation.

Checkpoint: the gradebook

Task: implement three methods against Dictionary<string, List<int>> (student → scores):

  1. static Dictionary<string, double> Averages(Dictionary<string, List<int>> gradebook) — each student's mean score (double division!). A student with an empty score list must NOT appear.
  2. static List<string> Honors(Dictionary<string, List<int>> gradebook) — students whose average is ≥ 90, ordered by descending average then ascending name.
  3. static string TopStudent(Dictionary<string, List<int>> gradebook) — the name with the highest average; on a tie, alphabetically first. Null/empty gradebook returns "".