如何在php中创建"122112211221"系列

Question

我需要$counter在我的循环中使用一个返回如下系列:

1 2 2 1 1 2 2 1

可悲的是,我对数学并不是那么好,无论我尝试什么都达到了死胡同.这是我尝试的最后一件事.

$counter = 0;

while( statement ) {
    ++$counter;

    // Making sure the second element is loaded
    if( $counter > 2 )
        $twoloaded = true;

    if( $counter >= 2 )
        --$counter;

    echo '<article class="post post-style-' . $counter . '"> ....... </article>';
}

最后我需要输出这样的HTML:

<article class="post post-style-1">
    ...
</article>

<article class="post post-style-2">
    ...
</article>

<article class="post post-style-2">
    ...
</article>

<article class="post post-style-1">
    ...
</article>

<article class="post post-style-1">
    ...
</article>

<article class="post post-style-2">
    ...
</article>

Answer 1

通用方法:

$pattern = [ 1, 2, 2, 1 ];   // or array( 1, 2, 2, 1 ); for PHP < 5.4
$idx = 0;

while ( expression ) {
    $number = $pattern[ $idx ++ % count( $pattern ) ];
}