
Sorting Algorithm

This is a sorting algorithm.   It may be applied to a set of data in order to sort it.    
For comparing various sorts, see compare sorts.  
For other sorting algorithms,   see sorting algorithms,   or:

O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort


Task

Bogosort a list of numbers.



Bogosort simply shuffles a collection randomly until it is sorted.

"Bogosort" is a perversely inefficient algorithm only used as an in-joke.

Its average run-time is   O(n!)   because the chance that any given shuffle of a set will end up in sorted order is about one in   n   factorial,   and the worst case is infinite since there's no guarantee that a random shuffling will ever produce a sorted sequence.

Its best case is   O(n)   since a single pass through the elements may suffice to order them.



Pseudocode:

while not InOrder(list) do
   Shuffle(list)
done



The Knuth shuffle may be used to implement the shuffle part of this algorithm.




MODE TYPE = INT;
 
PROC random shuffle = (REF[]TYPE l)VOID: (
    INT range = UPB l - LWB l + 1;
    FOR index FROM LWB l TO UPB l DO
        TYPE tmp := l[index];
        INT other := ENTIER (LWB l + random * range);
        l[index] := l[other];
        l[other] := tmp
    OD
);
 
PROC in order = (REF[]TYPE l)BOOL: (
    IF LWB l >= UPB l THEN
        TRUE
    ELSE
        TYPE last := l[LWB l];
        FOR index FROM LWB l + 1 TO UPB l DO
            IF l[index] < last THEN
                GO TO return false
            FI;
            last := l[index]
        OD;
        TRUE EXIT
        return false: FALSE
    FI
);
 
PROC bogo sort = (REF[]TYPE l)REF[]TYPE: (
    WHILE NOT in order(l) DO
        random shuffle(l)
    OD;
    l
);
 
[6]TYPE sample := (61, 52, 63, 94, 46, 18);
print((bogo sort(sample), new line))