将元素添加到 PHP 中的列表节点

Question

如果我有一个具有以下定义的列表节点

class ListNode {
      public $val = 0;
      public $next = null;
      function __construct($val = 0, $next = null) {
          $this->val = $val;
          $this->next = $next;
      }
  }

如何将元素添加到列表节点的末尾，从而通过交互添加 int[i] 元素？

Answer 1

class ListNode {

  public int $val = 0;
  public ?ListNode $next = null;

  function __construct(?int $val = 0, ?ListNode $next = null) {
    $this->val = $val;
    $this->next = $next;
  }

  function appendToListEnd(int $val) {
    if ($this->next == null) {
      $this->next = new ListNode($val);
    } else {
      $temp = $this->next;
      while ($temp->next != null) {
        $temp = $temp->next;
      }
      $temp->next = new ListNode($val);
    }
  }

}

$arr = [ 1, 2, 3, 4 ];

$listHead = new ListNode($arr[0]);

for ($i = 1; $i < count($arr); $i++) {
  $listHead->appendToListEnd($arr[$i]);
}
print_r($listHead);

$listHead->appendToListEnd(5);
print_r($listHead);

将元素添加到 PHP 中的列表节点

Add element to listnode in PHP

php

algorithm

data-structures