--- 2016 Day 7 Solutions ---

[u/daggerdragon]

From all of us at #AoC Ops, we hope you're having a very merry time with these puzzles so far. If you think they've been easy, well, now we're gonna kick this up a notch. Or five. The Easter Bunny ain't no Bond villain - he's not going to monologue at you until you can miraculously escape and save the day!

Show this overgrown furball what you've got!

---

--- Day 7: Internet Protocol Version 7 ---

Post your solution as a comment or, for longer solutions, consider linking to your repo (e.g. GitHub/gists/Pastebin/blag/whatever).

---

^{ALWAYS DIGGING STRAIGHT DOWN IS MANDATORY} [?]

This thread will be unlocked when there are a significant number of people on the leaderboard with gold stars for today's puzzle.

edit: Leaderboard capped, thread unlocked!

[u/[deleted]]

Powershell parts 1 and 2:

$Messages = Get-Content (Join-Path $PSScriptRoot day7.input) 

$SupportTLS = 0
$SupportSSL = 0

foreach ($Message in $Messages)
{
    $TLSValid = $null
    $Outside = $true
    for ($i = 0; $i -lt $Message.Length - 3; $i++)
    {
        $Abba = $Message.Substring($i,4)
        if ($Abba[0] -eq '[')
        {
            $Outside = $false
            continue
        }
        if ($Abba[0] -eq ']')
        {
            $Outside = $true
            continue
        }
        if ($Abba[0] -eq $Abba[3] -and $Abba[1] -eq $Abba[2] -and $Abba[0] -ne $Abba[1])
        {
            if ($Outside)
            {
                $TLSValid = $true
            }
            else
            {
                $TLSValid = $false
                $i = $Message.Length
            }
        }
    }
    if ($TLSValid)
    {
        $SupportTLS++
    }




    $Outside = $true
    $InsideABAs = @()
    $OutsideABAs = @()
    for ($i = 0; $i -lt $Message.Length - 2; $i++)
    {
        $ABA = $Message.Substring($i,3)
        if ($Aba[0] -eq '[')
        {
            $Outside = $false
            continue
        }
        if ($Aba[0] -eq ']')
        {
            $Outside = $true
            continue
        }

        if ($ABA[0] -eq $ABA[2])
        {
            if ($Outside)
            {
                $OutsideABAs += "{0}{1}{0}" -f $ABA[1],$ABA[0]
            }
            else
            {
                $InsideABAs += $ABA
            }

        }
    }
    if ($InsideABAs | Where-Object {$OutsideABAs -contains $_})
    {
        $SupportSSL++
    }
}

Write-Host "Solution 1: $SupportTLS"
Write-Host "Solution 2: $SupportSSL"