Lazy generate consecutive biggest products of two arrays

lazy-consecutive-biggest-product.php

<?php
function getAListProductIterator($aList, $aListSize, $bValue, $bIndex) {
  for ($aIndex=0; $aIndex < $aListSize; $aIndex++) {
    yield [
      'product' => $aList[$aIndex] * $bValue,
      'aIndex' => $aIndex,
      'bIndex' => $bIndex
    ];
  }
}

function getConsecutiveBiggestProducts($aList, $bList) {
  $aListSize = count($aList);
  $bListSize = count($bList);
  $n = $bListSize*$aListSize;

  rsort($aList);
  rsort($bList);

  $aIteratorsPriorityQueue = new SplPriorityQueue;

  for ($bIndex=0; $bIndex < $bListSize; $bIndex++) {
    $bValue = $bList[$bIndex];
    $aIteratorsPriorityQueue->insert(
      getAListProductIterator($aList, $aListSize, $bValue, $bIndex),
      $aList[0] * $bValue
    );
  }

  for ($i=0; $i < $n; $i++) {
    $aIterator = $aIteratorsPriorityQueue->extract();

    yield $aIterator->current();

    $aIterator->next();
    if($aIterator->valid()) {
      $aIteratorsPriorityQueue->insert(
        $aIterator,
        $aIterator->current()['product']
      );
    }
  }
}

$aList = array(3, 5, 24, 306, 48, 25, 25, 205);
$bList = array(0, 73, 48, 25, 1, 2, 3, 508, 401, 2, 200);

$abList1 = [];
foreach (getConsecutiveBiggestProducts($aList, $bList) as $value) {
  $abList1[] = $value['product'];
}

// Naive approach
$abList2 = [];
foreach($aList as $aKey => $a) {
  foreach($bList as $bKey => $b) {
    $abList2[] = $a*$b;
  }
}
rsort($abList2);

var_dump($abList1 === $abList2);