Day1

$strArray = $stringInput -split '\r\n\s'
$elfId = 1
$elfResults = foreach ($row in $strArray) {
    $elfCaloriesStrs,$elfCalories = $null
    $elfCaloriesStrs = $row -split '\s' | Where {-not [string]::IsNullOrWhiteSpace($_)}
    $elfCalories = ($elfCaloriesStrs | foreach {$_ -as [int]} | Measure-Object -Sum).Sum
    [pscustomobject]@{
        elf = $elfId
        Calories = $elfCalories
    }
    $elfId++
}
$elfResults | Sort Calories | Select -Last 1

# 2
($elfResults | Sort Calories -Descending | Select -First 3 | Measure-Object -Sum -Property Calories).Sum