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# Python Program for BogoSort or Permutation Sort

BogoSort also known as permutation sort, stupid sort, slow sort, shotgun sort or monkey sort is a particularly ineffective algorithm based on generate and test paradigm. The algorithm successively generates permutations of its input until it finds one that is sorted.(Wiki
For example, if bogosort is used to sort a deck of cards, it would consist of checking if the deck were in order, and if it were not, one would throw the deck into the air, pick the cards up at random, and repeat the process until the deck is sorted.
PseudoCode:

```while not Sorted(list) do
shuffle (list)
done```

## Python3

 `# Python program for implementation of Bogo Sort``import` `random` `# Sorts array a[0..n-1] using Bogo sort``def` `bogoSort(a):``    ``n ``=` `len``(a)``    ``while` `(is_sorted(a)``=``=` `False``):``        ``shuffle(a)` `# To check if array is sorted or not``def` `is_sorted(a):``    ``n ``=` `len``(a)``    ``for` `i ``in` `range``(``0``, n``-``1``):``        ``if` `(a[i] > a[i``+``1``] ):``            ``return` `False``    ``return` `True` `# To generate permutation of the array``def` `shuffle(a):``    ``n ``=` `len``(a)``    ``for` `i ``in` `range` `(``0``,n):``        ``r ``=` `random.randint(``0``,n``-``1``)``        ``a[i], a[r] ``=` `a[r], a[i]` `# Driver code to test above``a ``=` `[``3``, ``2``, ``4``, ``1``, ``0``, ``5``]``bogoSort(a)``print``(``"Sorted array :"``)``for` `i ``in` `range``(``len``(a)):``    ``print` `(``"%d"` `%``a[i]),`

Output:

```Sorted array :
0
1
2
3
4
5```

Time Complexity:

Worst Case: O(∞) (since this algorithm has no upper bound)
Average Case: O(n*n!)
Best Case: O(n)(when the array given is already sorted)

Auxiliary Space: O(1)

Method 2: BogoSort implementation using builtin shuffle() and sorted() function

In this implementation, the sorted built-in function is used to check if the list is sorted or not. The random.shuffle function is used to generate a permutation of the array a.

## Python3

 `import` `random`` ` `# Sorts array a[0..n-1] using Bogo sort``def` `bogoSort(a):``    ``n ``=` `len``(a)``    ``while` `not` `sorted``(a) ``=``=` `a:``        ``random.shuffle(a)`` ` `# Driver code to test above``a ``=` `[``3``, ``2``, ``4``, ``1``, ``0``, ``5``]``bogoSort(a)``print``(``"Sorted array:"``)``for` `i ``in` `range``(``len``(a)):``    ``print` `(``"%d"` `%``a[i]),`

Output

```Sorted array:
0
1
2
3
4
5```

Time Complexity:

Worst Case: O(∞) (since this algorithm has no upper bound)
Average Case: O(n*n!)
Best Case: O(n)(when the array given is already sorted)

Auxiliary Space: O(1)
Please refer complete article on BogoSort or Permutation Sort for more details!

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