# Looping through all combinations

• 07-16-2012, 11:54 PM
DavidB3ck
Looping through all combinations
Hi. I'm new here and such. It's been a few years since I've been on any coding forums, but this one seems to be the most active from the forums I remember.

Anyway, I know this has been discussed many times before, but what I'm trying to do is a little different, and I have yet to find or come up with any satisfactory solutions. Basically, given the array, `\$arr = array(0, 1, 2, 3, 4);`, I want to produce the following results:
Code:

```01234 0123 0124 0134 0234 1234 012 013 014 023 024 034 123 124 134 234 01 02 03 04 12 13 14 23 24 34 0 1 2 3 4```
The order of the elements in the array are from most to least important. In other words, the order of the results are from most to least important, or most to least similar to the original array.
Right now I can't even think of how to get started, so any help would be greatly appreciated.

Thanks!
• 07-17-2012, 04:26 AM
DrDOS
How similar this is to something I am working with/on! This is a problem in combinatorics, to give it a mathematical name. You have 5 distinct items, they can be ordered in 120 ways, you only want them ordered in 20 particular ways, quite interesting.