<?php

for ($i = 2004; $i <= 2022; $i++) {
    echo "$i<br/>";
}

echo "<br/><br/>";

$k = 2004;

while ($k <= 2022) {
    echo "$k<br/>";
    $k++;
}

$k = 2004;

echo "<br/><br/>";


do {
    echo "$k<br/>";
    $k++;
} while ($k <= 2022);