Comparing algorithms
Count how the steps grow as the data grows, and choose the right method.
Planned. This module is part of the plan and is not written yet.
Why it matters
The Lantern runs on two small computers serving many stations, so a method whose steps grow slowly as the data grows keeps every learner's screen quick.
Draft outline · in review- For
- Level 12–13 · SSS 3 (WASSCE) to A level / JUPEB / foundation year
- Inside
- 5 lessons and a test · about 75 minutes
- Topic
- Searching and sorting · extension, 3 of 4
Inside the module.
5 lessons in order, about 75 minutes in all, then a short test. Learners go at their own pace; the minutes are a guide, not a timetable.
Draft outline · in review
Lesson 1: Counting steps, not seconds
Why we measure how steps grow with n instead of timing one run.
Explain15 min, from minute 0
Lesson 2: O(n), O(log n), O(n log n), O(n²)
The growth rates of the searches and sorts you know.
Explain15 min, from minute 15
Lesson 3: Timing sorts as n grows
Time bubble sort and merge sort on growing lists and plot the results.
Investigate20 min, from minute 30
Lesson 4: Choosing the right tool
Small data, nearly sorted data, data searched often: which method fits?
Discussion15 min, from minute 50
Lesson 5: Check your skills
Match algorithms to growth rates and justify choices.
Review10 min, from minute 65
End-of-module test
Compare how the steps of different searches and sorts grow, and choose and justify a method for a given task.
Mastered at 85% or more. Retake it until you pass; nothing is lost, and each try gives feedback.
Already know it? A Challenge Test (planned) clears the whole module: 90% overall, no objective below 75%.
Last stageafter about 75 min
Practicalities
Draft outline · in reviewBuilt to run offline
Planned to run on the Lantern's own computer, with no internet needed.
Languages
Planned first in English; every module aims to reach all of the Lantern's languages.
Try a question.
One question from the module, as a learner would meet it. Have a go, then open the worked solution a step at a time.
Draft outline · in review
A list of 10,000 learner records changes rarely but is searched hundreds of times a day. Which approach is best?
Particulars
Where it sits
Coding · Algorithms & data structures · Searching and sorting
What a learner can do after it
- Compare how the number of steps grows for different searches and sorts.
- Choose a suitable search or sort for a task and justify it.
Level
Level 12–13 · SSS 3 (WASSCE) to A level / JUPEB / foundation year
Level mappings are approximate. A qualified teacher or lecturer in each country must check them before they appear in the app. Levels 13–18 describe the content, not the learner: “Level 15” means material usually taught in a second-year university course, whoever chooses to learn it.
Difficulty for its level
3 of 4 · Extension
Time
About 75 minutes
Alignments
- Aligned to CS2023partial · in reviewCS2023 Algorithmic Foundations: searching and sorting (descriptive ref)
Alignment in review until a qualified teacher or lecturer checks it. No exam body, university or vendor endorses us; learners still sit the real exam. University-level modules give knowledge, not university credit.
Challenge Test
Planned: a Challenge Test to prove you know it and skip it. Pass at 90% overall, with no objective below 75%.
University courses it previews
Computer Science, Software Engineering
On these pathways
The route here.
Everything this module builds on, drawn as a route from its foundations. Solid lanes must be mastered first, or cleared by a Challenge Test; dashed lanes are suggestions that never lock anything.
- CO-BLK-SEQ-01 Instructions in order, Level 1–4, Coding. Planned.
- CO-BLK-SEQ-01Instructions in orderCoding · Primary 1 to Primary 4 (Level 1–4) · Planned
- CO-BLK-LOP-01 Repeat blocks, Level 3–5, Coding. Sample lesson in the demo.
- CO-BLK-LOP-01Repeat blocksCoding · Primary 3 to Primary 5 (Level 3–5) · Sample lesson in the demo Needs Instructions in order (required).Try the sample lesson: Repeat blocks
- DS-CMP-TYP-01 The home row, Level 3–6, Digital skills. Planned.
- DS-CMP-TYP-01The home rowDigital skills · Primary 3 to Primary 6 (Level 3–6) · Planned · recommended
- CO-BLK-CND-01 If this, then that, Level 3–6, Coding. Planned.
- CO-BLK-CND-01If this, then thatCoding · Primary 3 to Primary 6 (Level 3–6) · Planned · recommended
- CO-BLK-LOP-02 Patterns with loops, Level 4–6, Coding. Planned.
- CO-BLK-LOP-02Patterns with loopsCoding · Primary 4 to Primary 6 (Level 4–6) · Planned Needs Repeat blocks (required).
- MA-ARI-ORD-01 Order of operations, Level 5–6, Maths. Planned.
- MA-ARI-ORD-01Order of operationsMaths · Primary 5 to Primary 6 (Level 5–6) · Planned · recommended
- CO-BLK-LOP-03 Loops inside loops, Level 5–7, Coding. Planned.
- CO-BLK-LOP-03Loops inside loopsCoding · Primary 5 to JSS 1 (Level 5–7) · Planned · recommended
- CO-PRG-PYB-01 Your first Python program, Level 7–9, Coding. Planned.
- CO-PRG-PYB-01Your first Python programCoding · JSS 1 to JSS 3 (BECE) (Level 7–9) · Planned Needs Patterns with loops (required), The home row (recommended).
- CO-PRG-PYB-02 Variables, Level 7–9, Coding. Sample lesson in the demo.
- CO-PRG-PYB-02VariablesCoding · JSS 1 to JSS 3 (BECE) (Level 7–9) · Sample lesson in the demo Needs Your first Python program (required).Try the sample lesson: Variables
- CO-PRG-PYB-03 Numbers and calculations, Level 7–9, Coding. Planned.
- CO-PRG-PYB-03Numbers and calculationsCoding · JSS 1 to JSS 3 (BECE) (Level 7–9) · Planned Needs Variables (required), Order of operations (recommended).
- MA-ALG-FRM-01 Substituting into formulae, Level 7–8, Maths. Planned.
- MA-ALG-FRM-01Substituting into formulaeMaths · JSS 1 to JSS 2 (Level 7–8) · Planned · recommended
- CO-PRG-PYB-05 Decisions with if, Level 8–10, Coding. Planned.
- CO-PRG-PYB-05Decisions with ifCoding · JSS 2 to SSS 1 (Level 8–10) · Planned Needs Numbers and calculations (required), If this, then that (recommended).
- CO-PRG-PYB-06 Loops in Python, Level 8–10, Coding. Planned.
- CO-PRG-PYB-06Loops in PythonCoding · JSS 2 to SSS 1 (Level 8–10) · Planned Needs Decisions with if (required), Loops inside loops (recommended).
- CO-PRG-PYF-01Defining functionsCoding · JSS 2 to SSS 2 (Level 8–11) · Planned Needs Loops in Python (required).
- CO-PRG-PYF-02Parameters and return valuesCoding · JSS 3 (BECE) to SSS 2 (Level 9–11) · Planned Needs Defining functions (required), Substituting into formulae (recommended).
- CO-ALG-SRT-01Linear searchCoding · JSS 3 (BECE) to SSS 2 (Level 9–11) · Planned Needs Parameters and return values (required), Lists (required).
- CO-PRG-PYF-03ScopeCoding · JSS 3 (BECE) to SSS 2 (Level 9–11) · Planned Needs Parameters and return values (required).
- CO-ALG-SRT-03Simple sortsCoding · SSS 1 to SSS 3 (WASSCE) (Level 10–12) · Planned Needs Linear search (required).
- CO-ALG-SRT-02Binary searchCoding · SSS 1 to SSS 3 (WASSCE) (Level 10–12) · Planned Needs Linear search (required).
- CO-PRG-PYF-05RecursionCoding · SSS 2 to A level / JUPEB / foundation year (Level 11–13) · Planned Needs Scope (required).
- CO-ALG-SRT-04Merge sortCoding · SSS 2 to A level / JUPEB / foundation year (Level 11–13) · Planned Needs Simple sorts (required), Recursion (required).
- CO-ALG-SRT-05Comparing algorithmsCoding · SSS 3 (WASSCE) to A level / JUPEB / foundation year (Level 12–13) · Planned · the destination Needs Binary search (required), Merge sort (required).
Help light the room where this is learned.
Every route on this map starts in a classroom with 24 stations, a tutor that works offline and a facilitator upstairs. Four are planned and waiting for light.