Unit 6 - Algorithms

An algorithm is a sequence of steps that can be followed to complete a task.

Removing unnecessary detail from a problem so that you can focus on the essentials.

Involves breaking down a large problem into smaller sub-problems.

Involves ‘Divide and Conquer’ The list is halved and halved until what you want is found. It has to be sorted before carrying out the search.

Examining the list one by one. You can do this if the list is unsorted. If it is, you can do a binary search. This method is not that efficient.

Each item is compared to the one next to it on the list. If it is bigger, it swaps places. At the end of one pass, the largest item would be on the list. This is repeated until the items are sorted

Binary and Linear search.

This algorithm sorts one data at a time. One item is taken from the list and put in the correct position This is repeated until the list is not unsorted.

This is much more efficient than bubble sort. Divide the unsorted list into sub lists, each containing 1 item Repeatedly merge two sub lists at a time to produce new sub lists until there is only one left. This would be the sorted sub-list

Merge Sort Insertion Sort Bubble Sort

A variable is a location in memory in which you can temporarily store text or numbers.

Sequence Selection Iteration