Algorithm Efficiency (AQA GCSE Computer Science)

Algorithm Efficiency

What is algorithm efficiency?

• Algorithm efficiency is how much time it takes to complete an algorithm

• In programming, there is often more than one algorithm which can solve a problem

• An example of this is a linear search and binary search as both find a value in a list, however, depending on the circumstances, one may be much faster than the other

Efficiency in action

• If we took the numbers 1-20 jumbled up in a list

• How efficient an algorithm is would be determined by how quickly it could sort the numbers into ascending order

• In the algorithms above, the worst case of a bubble sort is that it would take 361 comparisons to sort 20 items of data

• The worst case of an insertion sort with 20 items is that it would perform 190 comparisons

• This means that in this instance, although both algorithms perform the same job and achieve the same result, an insertion sort would be significantly faster because it is much more efficient in how it uses the computer’s processing power and memory