University of Auckland · S2 2026 · FACULTY OF COMPUTER SCIENCE

COMPSCI220 Algorithms and Data Structures

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The Complete Exam Bible · S2 2026

COMPSCI220 Overview

Algorithms and Data Structures
— A source-grounded COMPSCI220 guide to asymptotic analysis, Big-O bound, loop invariant and the complete published assessment structure.
  • School of Computer Science, University of Auckland
  • Semester Two, 2026
  • Stage 2 undergraduate course
  • 15 points

COMPSCI 220 Algorithms and Data Structures develops asymptotic analysis, sorting, recurrences, trees, heaps, hashing and graph algorithms. It is taught within School of Computer Science, University of Auckland. It is Stage 2 undergraduate course. It carries 15 points.

  • Three pass checks A student must pass practical work, pass the tests-and-exam theory component and pass overall; strength in one side cannot erase failure in another.
  • 15/35/50 architecture Practical work is 15%, the two tests total 35%, and the comprehensive final examination is 50%.
  • Scale is the question An algorithm can be correct on a small input yet unusable at scale; state the operation count and the input variable behind every growth claim.
Why read this guide

What you get in the full COMPSCI220 Exam Bible

  1. 6 chapters, 18 pages — every examinable topic, week by week
  2. 9 original practice questions, each with a model answer in the Final Examination format
  3. 6 worked examples, solved the way COMPSCI220 marks
  4. 14 computed figures, redrawn from the course’s own numbers
  5. Exam-morning plan for the Final Examination (50%) — what to revise last, where marks are lost

Free on this page: assessment table, chapter map, one worked example, key terms, FAQ. The rest is in the full exam bible.

COMPSCI220 · University of Auckland
An independent, AskSia-authored study guide. AskSia is not affiliated with, endorsed by, or sponsored by University of Auckland; the course code and name are used for identification only.
Assessment

How COMPSCI220 is assessed

ComponentWeightFormat
Practical Component · hurdle15%Mathematics prerequisite quiz, written and programming assignments, and tutorial presentations; this component must be passed
Tests35%Two midterm tests contributing 17.5% each to the theory component
Final Examination50%Comprehensive theory assessment covering the full course

Practical work contributes 15%, two tests contribute 35% and the final exam contributes 50%. Students must pass the practical component, the theory component formed by tests and exam, and the course overall.

Other students are asking · COMPSCI220

What other students are asking about COMPSCI220

Where can I find lecture notes or study guides for COMPSCI220 at Auckland?
The COMPSCI220 study guide in AskSia Library covers Algorithms and Data Structures in 6 chapters, with the assessment table, a chapter-by-chapter topic map, key terms and a worked example, free to read on this page.
Is there a final exam in COMPSCI220, and how much is it worth?
Yes. In the offering this AskSia Library guide is built from, Final Examination carries 50% of the COMPSCI220 mark; the full split is Practical Component 15%, Tests 35%, Final Examination 50%.
What does COMPSCI220 cover on sorting algorithms and recurrences?
In AskSia Library's COMPSCI220 guide, the Sorting Algorithms and Recurrences chapter explains comparison sort · recurrence · stability · trace a divide-and-conquer sort and solve or justify its recurrence at the required scale.
What does COMPSCI220 cover on heaps and search trees?
In AskSia Library's COMPSCI220 guide, the Heaps and Search Trees chapter explains heap · binary search tree · tree height · execute insertion or removal and explain how structural height controls running time.
What does COMPSCI220 cover on hashing and collision control?
In AskSia Library's COMPSCI220 guide, the Hashing and Collision Control chapter explains hash function · load factor · collision resolution · trace insertions through collisions and relate load factor to expected access cost.
Weights, dates and every chapter are set out with their sources further down this page.
Contents · every chapter, one map

What COMPSCI220 covers

Build the course in three arcs: Asymptotic Analysis and Correctness establishes the frame, Hashing and Collision Control deepens it, and Weighted Graphs, Shortest Paths and Spanning Trees tests the complete method.

01

Asymptotic Analysis and Correctness

asymptotic analysis · Big-O bound · loop invariant · prove a simple loop result and derive an asymptotic bound from its operation count

Define asymptotic analysis

The course material gives this chapter a concrete anchor: The opening materials connect mathematical prerequisites, program-performance analysis and correctness before individual data structures are introduced.

  • asymptotic analysis
  • Big-O bound
  • loop invariant
  • Applying asymptotic analysis
  • Limits of Big-O bound and loop invariant
In the full guide: 2 pages · 1 practice question · 2 figures
02

Sorting Algorithms and Recurrences

comparison sort · recurrence · stability · trace a divide-and-conquer sort and solve or justify its recurrence at the required scale

Define comparison sort

The course material gives this chapter a concrete anchor: Two sorting weeks and the landed solution material connect algorithm traces with recurrence and comparison-cost reasoning.

  • comparison sort
  • recurrence
  • stability
  • Applying comparison sort
  • Limits of recurrence and stability
In the full guide: 3 pages · 1 practice question · 2 figures
03

Heaps and Search Trees

heap · binary search tree · tree height · execute insertion or removal and explain how structural height controls running time

Define heap

The course material gives this chapter a concrete anchor: Week 4 and the review material compare tree structures and operations, making height the mechanism behind efficient or degraded performance.

  • heap
  • binary search tree
  • tree height
  • Applying heap
  • Limits of binary search tree and tree height
In the full guide: 2 pages · 1 practice question · 1 figure
04

Hashing and Collision Control

hash function · load factor · collision resolution · trace insertions through collisions and relate load factor to expected access cost

Define hash function

The course material gives this chapter a concrete anchor: The current hashing week and tutorial answers provide collision and table-state practice grounded in actual operations rather than a generic dictionary analogy.

  • hash function
  • load factor
  • collision resolution
  • Applying hash function
  • Limits of load factor and collision resolution
In the full guide: 3 pages · 1 practice question · 2 figures
05

Graph Traversal and Components

graph representation · breadth-first search · connected component · trace a traversal, record its discovery structure and identify reachable components

Define graph representation

The course material gives this chapter a concrete anchor: The course schedule and solution material place traversal and connected-component reasoning before weighted optimisation, preserving the distinction between reachability and path cost.

  • graph representation
  • breadth-first search
  • connected component
  • Applying graph representation
  • Limits of breadth-first search and connected component
In the full guide: 2 pages · 1 practice question · 2 figures
06

Weighted Graphs, Shortest Paths and Spanning Trees

edge relaxation · shortest path · minimum spanning tree · execute relaxation and distinguish a shortest-path tree from a minimum spanning tree

Define edge relaxation

The course material gives this chapter a concrete anchor: Weeks 10-12 in the schedule cover weighted graphs, single-source and all-pairs shortest paths and spanning trees, so their objectives and assumptions must be compared explicitly.

  • edge relaxation
  • shortest path
  • minimum spanning tree
  • Applying edge relaxation
  • Limits of shortest path and minimum spanning tree
In the full guide: 3 pages · 1 practice question · 2 figures

It is positioned as Compulsory for Computer Science majors according to the current public course page.

The course combines implementation with hand execution and proof-oriented efficiency analysis; passing requires practical and theory performance separately as well as an overall pass.

Assessment in COMPSCI220 is distributed as follows: Practical work contributes 15%, two tests contribute 35% in total, and the final examination contributes 50%.

The captured detailed breakdown assigns 1% to a mathematics prerequisite quiz, 5% to written assignments, 5% to programming assignments and 4% to tutorial presentations.

The operational assessment conditions matter here. Tests and the final examination form the theory component.

Attendance on campus is required for tests and the examination, but Semester Two sitting details must be checked in the live course site and official timetable.

What makes COMPSCI220 demanding is concrete: The central challenge is to move between code, an operation trace and an asymptotic argument: a correct output on one input is not enough without a reason the algorithm remains correct and scales as claimed.

Students must pass the practical component, pass the theory component made from tests and examination, and achieve an overall pass.

For enrolment planning, COMPSCI 120 and COMPSCI 130 are prerequisites; COMPSCI 717 and SOFTENG 284 are restrictions in the landed course syllabus.

Build the course in three arcs: Asymptotic Analysis and Correctness establishes the frame, Hashing and Collision Control deepens it, and Weighted Graphs, Shortest Paths and Spanning Trees tests the complete method.

Worked example · free

Trace a shortest-path relaxation step

Q [4 marks]. In an AskSia-authored weighted graph, d(u)=7, d(v)=12 and edge (u,v) has weight 3. Apply one relaxation and explain the condition.
Figure.Figure. graph representation, breadth-first search and connected component define the route to graph-reachability trace.graph representationbreadth-first searchconnected componentgraph-reachability trace
Figure. graph representation, breadth-first search and connected component define the route to graph-reachability trace.
  • 1Compute the candidate distance through u as 7 plus 3, giving 10.
  • 1Compare the candidate 10 with the current value 12.
  • 1Update d(v) to 10 and set u as the predecessor because the candidate is smaller.
  • 1State that a non-improving candidate leaves both records unchanged and that algorithm assumptions on edge weights still matter.
Relaxation changes d(v) from 12 to 10 and records u as its predecessor. The assignment is conditional on 7+3 being smaller than 12; the step alone does not prove that 10 is globally final unless the surrounding shortest-path algorithm permits that conclusion.
Sia tip — Separate a tentative improvement from proof that a distance is final.
Glossary

Key terms

Asymptotic analysis
The study of how an algorithm's time or space requirement grows with input size while ignoring fixed implementation constants.
Shortest path
A path between vertices with minimum total edge weight among the paths allowed by the graph and algorithm assumptions.
Recurrence
An equation defining a problem's cost or value in terms of smaller instances together with one or more base cases.
Heap
A complete-tree data structure whose parent-child ordering supports efficient access to and removal of an extreme-priority element.
Binary search tree
A binary tree maintaining an ordering relation between each node and the keys stored in its left and right subtrees.
Hash table
A mapping structure that uses a hash function and collision strategy to place and retrieve keys in an indexed table.
Graph traversal
A systematic process such as breadth-first or depth-first search for visiting vertices and edges while recording discovery structure.
FAQ

COMPSCI220 FAQ

What prerequisites or restrictions apply to COMPSCI220?

COMPSCI 120 and COMPSCI 130 are prerequisites; COMPSCI 717 and SOFTENG 284 are restrictions in the landed course syllabus.

Does COMPSCI220 have a hurdle or component-level pass rule?

Students must pass the practical component, pass the theory component made from tests and examination, and achieve an overall pass.

Where do students usually lose marks in COMPSCI220?

The central challenge is to move between code, an operation trace and an asymptotic argument: a correct output on one input is not enough without a reason the algorithm remains correct and scales as claimed.

How is COMPSCI220 assessed?

Practical work contributes 15%, two tests contribute 35% in total, and the final examination contributes 50%. The captured detailed breakdown assigns 1% to a mathematics prerequisite quiz, 5% to written assignments, 5% to programming assignments and 4% to tutorial presentations.

What is the COMPSCI220 exam or final-task format?

Tests and the final examination form the theory component. Attendance on campus is required for tests and the examination, but Semester Two sitting details must be checked in the live course site and official timetable.

Which offering does this COMPSCI220 guide cover?

It is aligned to Semester Two, 2026; confirm your enrolled class and timetable in the current institutional system.

Is this COMPSCI220 resource an official university guide?

No. It is an independent COMPSCI220 study resource; current institutional instructions remain authoritative for assessment operation.

Chapter questions

Questions students ask in each COMPSCI220 chapter

What is the main task in Asymptotic Analysis and Correctness?
Prove a simple loop result and derive an asymptotic bound from its operation count. Chapter 01 · Asymptotic Analysis and Correctness
What is the main task in Sorting Algorithms and Recurrences?
Trace a divide-and-conquer sort and solve or justify its recurrence at the required scale. Chapter 02 · Sorting Algorithms and Recurrences
What is the main task in Heaps and Search Trees?
Execute insertion or removal and explain how structural height controls running time. Chapter 03 · Heaps and Search Trees
What is the main task in Hashing and Collision Control?
Trace insertions through collisions and relate load factor to expected access cost. Chapter 04 · Hashing and Collision Control
What is the main task in Graph Traversal and Components?
Trace a traversal, record its discovery structure and identify reachable components. Chapter 05 · Graph Traversal and Components
What is the main task in Weighted Graphs, Shortest Paths and Spanning Trees?
Execute relaxation and distinguish a shortest-path tree from a minimum spanning tree. Chapter 06 · Weighted Graphs, Shortest Paths and Spanning Trees
Study strategy

How to study for the exam

Retrieve the course map, practise the recurring method—state the input representation and correctness condition, trace the algorithm on a boundary case, derive its time or space growth from counted operations and test whether the data-structure or graph assumptions support the conclusion—on changed scenarios, and verify every operational assessment detail in the live institutional system.

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