Test list of IP addresses

#########################################################
#                                                       #
#       This script will do the following;              #
#        - Read in a list of IP addresses               #
#        - Strip off any port numbers                   #
#        - Remove duplicate IP addresses                #
#        - Test the connection to each IP               #
#        - Report the connection speed to each one      #
#                                                       #
#########################################################

# Prepare the results file
"IP Address, response time" | out-file -FilePath "c:\temp\results.csv"  -encoding utf8

# Create the array for holding the list of addresses.
$LIST = new-object system.collections.arraylist

# Read in the list of addresses
foreach ($line in get-content c:\temp\addresses.txt) {$LIST.add("$line")}

# Remove any port suffixes
$count=0;while ($count -lt $LIST.count){$LIST[$count]=$LIST[$count].split(":")[0];$count++}

# Remove duplicates
$count=0
while ($count -lt $LIST.count)
{
        if ($list[$count] -eq $list[$count+1])
            {
              $list.removeat($count+1)
              $count++
            }
            else
            {
            $count++
            }
}


# Test each IP
foreach ($line in $LIST)
{
    $test=test-connection -count 1 -quiet $line
    if ($test -eq $False)
    {
        write-host -foregroundcolor yellow $line,Failed
        "$line`tFailed" | out-file -append -filepath "c:\temp\results.csv" -encoding utf8
    }
 else
    {
    $test=test-connection -count 1 $line
    $responsetime=$test.responsetime
    write-host $line, $responsetime
    write-output "$line`t$responsetime" | out-file -append -filepath "c:\temp\results.csv" -encoding utf8
    }
}