Bubble sort in PHP

bubble-sort-in-php.php

<?php

function bubbleSort(array $a): array
{
  for ($i = count($a) - 1; $i > 0; $i--) {
    for ($j = 0; $j < $i; $j++) {
      if ($a[$j] > $a[$j + 1]) { 
        $temp = $a[$j];
        $a[$j] = $a[$j+1];
        $a[$j+1] = $temp;
      }
    }
  }
  return $a;
}

// $bs = [5, 2, 8, 9, 1];
// bubbleSort($bs);
// [1, 2, 5, 8, 9]

function bubbleSortOptimized(array $a): array
{
  for ($i = count($a) - 1; $i > 0; $i--) {
    $swap = false;
    for ($j = 0; $j < $i; $j++) {
      if ($a[$j] > $a[$j + 1]) { 
        $temp = $a[$j];
        $a[$j] = $a[$j+1];
        $a[$j+1] = $temp;
        $swap = true;
      }
    }
    if (!$swap) break;
  }
  return $a;
}

// $bs = [6, 1, 2, 3, 4, 5];
// bubbleSortOptimized($bs);
// [1, 2, 3, 4, 5, 6]