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Free module

Algorithms and complexity

Learn algorithms and complexity hands on: count steps, search, sort, write recursion, memoise answers and find paths in graphs.

6 lessons375 min lessonCore computer science

The lessons

Each lesson is free to read in full. Create a free account to run its commands in a live lab and to sit its quizzes and tasks.

  1. 1 · Virtual machine lab

    Time complexity and counting steps

    I can count the steps of an algorithm and say how the count grows.

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  2. 2 · Virtual machine lab

    Linear search and binary search

    I can compare linear search and binary search by the steps they take.

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  3. 3 · Virtual machine lab

    Insertion, selection and merge sort

    I can trace insertion sort, selection sort and merge sort and compare what they cost.

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  4. 4 · Virtual machine lab

    Recursion and the call stack

    I can write a recursive function with a base case.

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  5. 5 · Virtual machine lab

    Memoisation and dynamic programming

    I can speed up a slow recursion by remembering answers.

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  6. 6 · Virtual machine lab

    Breadth-first search in graphs

    I can find a path with breadth-first search.

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Worked in a real lab

Every lesson of this module is worked in a lab started for you alone. The labs it uses:

Teaching a class? Set this module for your students with a teacher guide, marked assignments and a lab for every student.