Day6

[char[]]$stream ??= $puzzleInput -split '\n' | Select -SkipLast 1

Function Get-Header {
    Param($stream,$uniqueCount)
    Process {
        $queue = [System.Collections.Queue]::new()
        for ($i = 0; $i -lt $stream.count; $i++) {
            [void]$queue.Enqueue($stream[$i])
            if (($queue | group).Name.count -eq $uniqueCount) {break}
            if (($queue.count % $uniqueCount) -eq 0) {$queue.Dequeue()}
        }
        $i+1
    }
}

Get-Header $stream 4
# Part 2
Get-Header $stream 14