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Software Engineering vocabulary · Data Structures and Algorithms

Space complexity

Meaning in software engineering, with examples

nounAdvanced term

In software engineering, space complexity means: How much extra memory an algorithm needs as its input grows, usually written in Big O notation, for example O(1) or O(n).

In Turkish: alan karmaşıklığı, bellek karmaşıklığı

How it is used

Usually discussed together with time complexity: 'What's the time and space complexity?' is a standard interview question. There is often a trade-off, because using more memory, for example a cache or a hash map, can make an algorithm faster.

Example sentences

  1. This version is faster, but its space complexity is O(n) because of the extra array.

  2. Can you reduce the space complexity to O(1) by sorting in place?

Common collocations

  • time and space complexity
  • constant space
  • reduce space complexity
  • O(1) space
  • time complexityHow the number of steps an algorithm takes grows as the size of its input grows, usually written in Big O notation.
  • Big O notationA way of describing how the running time or memory use of an algorithm grows as the input gets bigger, for example O(1), O(n) or O(n²).
  • algorithmA clear, step-by-step method for solving a problem or doing a task, such as sorting a list or finding the shortest route between two points.
  • trade-offA situation where getting more of one good thing means accepting less of another, such as speed versus accuracy or simplicity versus flexibility.

More terms: Data Structures and Algorithms

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