How to make all unique sequences from one dimensional array?

Question

PHP

There is an array: (1, 2, 3), you need to get all unique sequences, while all elements of the array must be involved, for example:

123
132
213
231
312
321

The array can be of any size. If the array, for example, is: (1, 2, 3, 4), then the result is:

1234
1243
...

Answer 1

docstore.mik.ua/orelly/webprog/pcook/ch04_26.htm

Answer 2

Combinatorics, permutations .