Summary: Learn how to get unique numbers from an array.
How can I use Windows PowerShell to return only the numbers that are unique in an array?
Sort the array of numbers, then pipe the output to the Get-Unique cmdlet, for example:
$a = 1,2,7,6,4,3,3,2,9
$a | sort | Get-Unique
Note Sort is an alias for the Sort-Object cmdlet.