SharePoint compare list values with PowerShell

SPCompareListValue.ps1

$mSite = Get-SPweb "http://sharepointed.com/site/taco"
$aList = $mSite.lists["A"]
$bList = $mSite.lists["B"]

$arrA = @()
$arrB = @()

foreach($iA in $aList.Items)
{
 $arrA += $iA["Title"]
}

foreach($iB in $bList.Items)
{
 $arrB += $iB["Title"]
}

$c = Compare-Object -ReferenceObject $arrA -DifferenceObject $arrB -PassThru
Write-Host $c