How do I get all the possible combinations of neighboring items in a subsequent order using Perl?

Programmer Question

For example, I have an array

my @arr = qw(0 1 2 3 4);

How do I get the following combinations:

0
01
012
0123
01234
1
12
123
1234
2
23
234
3
34
4

If any, what's the name for this kind of combination (or permutation)?

Thanks like always!

Find the answer here