TheAlgorithms-Ruby/README.md

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2016-08-16 16:35:33 +02:00
# The Algorithms - Ruby
### All algorithms implemented in Ruby (for education)
These are for demonstration purposes only.
## Sorting Algorithms
### Bogo Sort
Add comments here
### Bubble Sort
![alt text][bubble-image]
From [Wikipedia][bubble-wiki]: Bubble sort, sometimes referred to as sinking sort, is a simple sorting algorithm that repeatedly steps through the list to be sorted, compares each pair of adjacent items and swaps them if they are in the wrong order. The pass through the list is repeated until no swaps are needed, which indicates that the list is sorted.
__Properties__
* Worst case performance O(n^2)
* Best case performance O(n)
* Average case performance O(n^2)
###### View the algorithm in [action][bubble-toptal]
### Insertion Sort
![alt text][insertion-image]
From [Wikipedia][insertion-wiki]: Insertion sort is a simple sorting algorithm that builds the final sorted array (or list) one item at a time. It is much less efficient on large lists than more advanced algorithms such as quicksort, heapsort, or merge sort.
__Properties__
* Worst case performance O(n^2)
* Best case performance O(n)
* Average case performance O(n^2)
###### View the algorithm in [action][insertion-toptal]
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### Selection Sort
![alt text][selection-image]
From [Wikipedia][selection-wiki]: The algorithm divides the input list into two parts: the sublist of items already sorted, which is built up from left to right at the front (left) of the list, and the sublist of items remaining to be sorted that occupy the rest of the list. Initially, the sorted sublist is empty and the unsorted sublist is the entire input list. The algorithm proceeds by finding the smallest (or largest, depending on sorting order) element in the unsorted sublist, exchanging (swapping) it with the leftmost unsorted element (putting it in sorted order), and moving the sublist boundaries one element to the right.
__Properties__
* Worst case performance O(n^2)
* Best case performance O(n^2)
* Average case performance O(n^2)
###### View the algorithm in [action][selection-toptal]
2017-09-28 18:58:56 +02:00
### Shell Sort
![alt text][shell-image]
From [Wikipedia][shell-wiki]: Shellsort, also known as Shell sort or Shell's method, is an in-place comparison sort. It can be seen as either a generalization of sorting by exchange (bubble sort) or sorting by insertion (insertion sort).[3] The method starts by sorting pairs of elements far apart from each other, then progressively reducing the gap between elements to be compared. Starting with far apart elements, it can move some out-of-place elements into position faster than a simple nearest neighbor exchange. Donald Shell published the first version of this sort in 1959.[4][5] The running time of Shellsort is heavily dependent on the gap sequence it uses. For many practical variants, determining their time complexity remains an open problem.
__Properties__
* Worst case performance O(n^2)
* Best case performance O(n log n)
* Average case performance depends on gap sequence
###### View the algorithm in [action][shell-toptal]
2017-09-28 15:28:07 +02:00
[selection-toptal]: https://www.toptal.com/developers/sorting-algorithms/selection-sort
[selection-wiki]: https://en.wikipedia.org/wiki/Selection_sort
[selection-image]: https://upload.wikimedia.org/wikipedia/commons/thumb/b/b0/Selection_sort_animation.gif/250px-Selection_sort_animation.gif "Selection Sort Sort"
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[bubble-toptal]: https://www.toptal.com/developers/sorting-algorithms/bubble-sort
[bubble-wiki]: https://en.wikipedia.org/wiki/Bubble_sort
[bubble-image]: https://upload.wikimedia.org/wikipedia/commons/thumb/8/83/Bubblesort-edited-color.svg/220px-Bubblesort-edited-color.svg.png "Bubble Sort"
[insertion-toptal]: https://www.toptal.com/developers/sorting-algorithms/insertion-sort
[insertion-wiki]: https://en.wikipedia.org/wiki/Insertion_sort
[insertion-image]: https://upload.wikimedia.org/wikipedia/commons/7/7e/Insertionsort-edited.png "Insertion Sort"
2017-09-28 18:58:56 +02:00
[shell-toptal]: https://www.toptal.com/developers/sorting-algorithms/shell-sort
[shell-wiki]: https://en.wikipedia.org/wiki/Shellsort
[shell-image]: https://upload.wikimedia.org/wikipedia/commons/thumb/4/4c/Shell_sorting_algorithm_color_bars.svg/267px-Shell_sorting_algorithm_color_bars.svg.png "Shell Sort"