PHP中的基数排序算法详解

function radixSort($array) {
    // 获取最大值
    $max = max($array);
    
    // 获取最大值的位数
    $numDigits = strlen((string) $max);
    
    // 创建桶数组
    $buckets = array_fill(0, 10, []);
    
    for ($i = 0; $i < $numDigits; $i++) {
        // 将数字分配到桶中
        foreach ($array as $num) {
            $digit = floor($num / pow(10, $i)) % 10;
            $buckets[$digit][] = $num;
        }
        
        // 将数字从桶中取出，并按顺序放回原数组
        $array = [];
        for ($j = 0; $j < 10; $j++) {
            foreach ($buckets[$j] as $num) {
                $array[] = $num;
            }
            $buckets[$j] = [];
        }
    }
    
    return $array;
}

// 测试排序算法
$array = [23, 6, 78, 12, 456, 2, 56, 11];
$result = radixSort($array);

echo "排序前：";
print_r($array);

echo "排序后：";
print_r($result);

[0] => 23
[1] => 6
[2] => 78
[3] => 12
[4] => 456
[5] => 2
[6] => 56
[7] => 11

[0] => 2
[1] => 6
[2] => 11
[3] => 12
[4] => 23
[5] => 56
[6] => 78
[7] => 456