permutation : Java Glossary

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permutation

If you take a set of objects and rearrange the order without taking any away or adding any, that is a permutation of the orginal set of objects. Permutations care about order where combinations do not. If you have n objects there are n! possible permutations of them.

Permutation Example

For example, the 3! = 6 permutations of three objects a, b and c are:

a	b	c
a	c	b
b	a	c
b	c	a
c	a	b
c	b	a

Dijkstra Algorithm

For code to generate them all see the Dijkstra algorithm. Here is an implemenation of the Dijkstra algorithm for permutations and also a combinations algorithm: view

Books

recommend book⇒A Discipline of Programming

by:

Edsger Wybe Dijkstra

978-0-13-215871-8

paperback

(born: 1930-05-11 died: 2002-08-06 at age: 72)

978-0-613-92411-5

hardcover

publisher:

Prentice Hall

published:

1976-10-28

See page 71 for the permutations algorithm.

Greyed out stores probably do not have the item in stock

combinations
factorial
pseudo-random numbers
shuffle
Uncommon Maths: a library of permutation generators

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