PHP數組只顯示最后一次推送的值

我做了一個php腳本，你必須在其中添加一些東西到你的bucketlist中，但是它不能正常工作。輸出的是最后一個輸入的bucketlist值。

<?php
echo "How much activities would you like to add?\n";
$a = readline ();
$d = "What do you want to add to your bucket list?\n";

if (is_numeric($a)) {
    for ($x = 1; $x <= $a; $x++) {
        echo $d;
        $c = readline();
    }
} else {
    echo "'$a' isn't a number, try again.";
    exit;
}

$bucketlist = [$c];
array_push($bucketlist);

foreach ($bucketlist as $z) {
    echo "On your bucket list:\n";
    echo $z;
    echo "\n";
}
?>

我需要它來輸出在readline$c中輸入的所有內容