Parsing the PHP standard library SPL data structure
SPL provides doubly linked lists, stacks, queues, heaps, descending heaps, ascending heaps, priority queues, fixed-length arrays, and object containers
SplQueue queue class
In and out, first in, first out
<?php$obj = new SplQueue();//插入一个节点到top位置$obj->enqueue(1);
$obj->enqueue(2);
$obj->enqueue(3);/**
SplQueue Object
(
[flags:SplDoublyLinkedList:private] => 4
[dllist:SplDoublyLinkedList:private] => Array
(
[0] => 1
[1] => 2
[2] => 3
)
)
*/$obj->offsetSet(0,'C');/**
SplQueue Object
(
[flags:SplDoublyLinkedList:private] => 4
[dllist:SplDoublyLinkedList:private] => Array
(
[0] => 'C'
[1] => 2
[2] => 3
)
)
*/$obj->rewind();//从队列中返回并删除bottom位置的元素$obj->dequeue();/**
'C'
SplQueue Object
(
[flags:SplDoublyLinkedList:private] => 4
[dllist:SplDoublyLinkedList:private] => Array
(
[0] => 2
[1] => 3
)
)
*/复制代码SplStack stack class
When entering and exiting single-ended, Last in, first out, first in, last out
$obj = new SplStack();/**
SplStack Object
(
[flags:SplDoublyLinkedList:private] => 6
[dllist:SplDoublyLinkedList:private] => Array
(
)
)
*///向堆栈放入一个节点到top位置$obj->push(1);
$obj->push(2);
$obj->push(3);/**
SplStack Object
(
[flags:SplDoublyLinkedList:private] => 6
[dllist:SplDoublyLinkedList:private] => Array
(
[0] => 1
[1] => 2
[2] => 3
)
)
*///堆栈的offset = 0 是Top所在的位置，offset = 1 是top节点靠近bottom位置的相邻节点$obj->offsetSet(0,'C');/**
SplStack Object
(
[flags:SplDoublyLinkedList:private] => 6
[dllist:SplDoublyLinkedList:private] => Array
(
[0] => 1
[1] => 2
[2] => 'C'
)
)
*/$obj->offsetSet(1,'B');/**
SplStack Object
(
[flags:SplDoublyLinkedList:private] => 6
[dllist:SplDoublyLinkedList:private] => Array
(
[0] => 1
[1] => 'B'
[2] => 'C'
)
)
*///堆栈的rewind使指针指向top节点，而双向链表的rewind指向bottom节点$obj->rewind();//堆栈的next是使指针向bottom方向相邻的节点移动一位，而链表是向top方向移动$obj->next();//遍历堆栈$obj->rewind();while($obj->valid()){ echo $obj->key().'=>'.$obj->current();
$obj->next();
}/**
2=>'C'
1=>'B'
0=>1
*///从堆栈中取出top位置的节点并删除$obj->pop();复制代码SplDoublyLinkedList Doubly linked list class
$obj = new SplDoublyLinkedList();//SplDoublyLinkedList Object ( [flags:SplDoublyLinkedList:private] => 0 [dllist:SplDoublyLinkedList:private] => Array ( ) )//把新的节点数据添加到链表的顶部Top$obj->push(1);
$obj->push(2);
$obj->push(3);//把新的节点数据添加到链表底部bottom$obj->unshift(4);/**
SplDoublyLinkedList Object
(
[flags:SplDoublyLinkedList:private] => 0
[dllist:SplDoublyLinkedList:private] => Array
(
[0] => 4
[1] => 1
[2] => 2
[3] => 3
)
)
*///在没有调用rewind()方法之前输出为nullecho 'current'.$obj->current();//输出: null//把指针指向bottom节点$obj->rewind();//获取当前指针指向的节点$obj->current();//输出: 4//将执行挪到下一个$obj->next();
$obj->current();//输出: 1$obj->prev();
$obj->current();//输出: 4//越界了$obj->next();
$obj->next();
$obj->next();
$obj->next();
$obj->current();//输出: null//判断当前节点是否有效$obj->valid()//输出： false$obj->prev();
$obj->valid()//输出： true$obj->shift();//把top节点从链表中删除并返回$obj->pop();//输出 3//把bottom节点从链表中删除并返回$obj->shift();//输出 4//返回top节点$obj->top();//返回bottom节点$obj->bottom();复制代码Thanks If your reading is helpful to you, please follow "CRMEB". There are our open source mall projects and knowledge payment projects on Code Cloud, which are all developed based on PHP vue. You are welcome to use them for learning and research. Follow us to stay in touch!
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