php 08_stack

Author: Hkesd

php/06_linkedlist/SingleLinkedList.php

@@ -133,7 +133,7 @@ public function getPreNode(SingleLinkedListNode $node)
  $preNode = $this->head;
  // 遍历找到前置节点 要用全等判断是否是同一个对象
  // http://php.net/manual/zh/language.oop5.object-comparison.php
- while ($curNode !== $node) {
+ while ($curNode !== $node && $curNode != null) {
  $preNode = $curNode;
  $curNode = $curNode->next;
  }

php/08_stack/.gitkeep

@@ -0,0 +1,159 @@
+<?php
+/**
+ * User: lide01
+ * Date: 2018/10/11 19:37
+ * Desc:
+ */
+
+namespace Algo_08;
+
+
+use Algo_06\SingleLinkedListNode;
+
+class StackOnLinkedList
+{
+ /**
+ * 头指针
+ *
+ * @var SingleLinkedListNode
+ */
+ public $head;
+
+ /**
+ * 栈长度
+ *
+ * @var
+ */
+ public $length;
+
+ /**
+ *
+ * StackOnLinkedList constructor.
+ */
+ public function __construct()
+ {
+ $this->head = new SingleLinkedListNode();
+ $this->length = 0;
+ }
+
+ /**
+ * 出栈
+ *
+ * @return bool
+ */
+ public function pop()
+ {
+ if (0 == $this->length) {
+ return false;
+ }
+
+ $this->head->next = $this->head->next->next;
+ $this->length--;
+
+ return true;
+ }
+
+ /**
+ * 入栈
+ *
+ * @param $data
+ *
+ * @return SingleLinkedListNode|bool
+ */
+ public function push($data)
+ {
+ return $this->pushData($data);
+ }
+
+ /**
+ * 入栈 node
+ *
+ * @param SingleLinkedListNode $node
+ *
+ * @return bool
+ */
+ public function pushNode(SingleLinkedListNode $node)
+ {
+ if (null == $node) {
+ return false;
+ }
+
+ $node->next = $this->head->next;
+ $this->head->next = $node;
+
+ $this->length++;
+ return true;
+ }
+
+ /**
+ * 入栈 data
+ *
+ * @param $data
+ *
+ * @return SingleLinkedListNode|bool
+ */
+ public function pushData($data)
+ {
+ $node = new SingleLinkedListNode($data);
+
+ if (!$this->pushNode($node)) {
+ return false;
+ }
+
+ return $node;
+ }
+
+ /**
+ * 获取栈顶元素
+ *
+ * @return SingleLinkedListNode|bool|null
+ */
+ public function top()
+ {
+ if (0 == $this->length) {
+ return false;
+ }
+
+ return $this->head->next;
+ }
+
+ /**
+ * 打印栈
+ */
+ public function printSelf()
+ {
+ if (0 == $this->length) {
+ echo 'empty stack' . PHP_EOL;
+ return;
+ }
+
+ echo 'head.next -> ';
+ $curNode = $this->head;
+ while ($curNode->next) {
+ echo $curNode->next->data . ' -> ';
+
+ $curNode = $curNode->next;
+ }
+ echo 'NULL' . PHP_EOL;
+ }
+
+ /**
+ * 获取栈长度
+ *
+ * @return int
+ */
+ public function getLength()
+ {
+ return $this->length;
+ }
+
+ /**
+ * 判断栈是否为空
+ *
+ * @return bool
+ */
+ public function isEmpty()
+ {
+ return $this->length > 0 ? false : true;
+ }
+}

php/08_stack/StackOnLinkedList.php

@@ -0,0 +1,32 @@
+<?php
+/**
+ * User: lide01
+ * Date: 2018/10/11 20:01
+ * Desc:
+ */
+
+namespace Algo_08;
+
+require_once '../vendor/autoload.php';
+
+$stack = new StackOnLinkedList();
+$stack->pushData(1);
+$stack->pushData(2);
+$stack->pushData(3);
+$stack->pushData(4);
+var_dump($stack->getLength());
+$stack->printSelf();
+
+$topNode = $stack->top();
+var_dump($topNode->data);
+
+$stack->pop();
+$stack->printSelf();
+$stack->pop();
+$stack->printSelf();
+
+var_dump($stack->getLength());
+
+$stack->pop();
+$stack->pop();
+$stack->printSelf();

php/08_stack/main.php

@@ -1,16 +1,20 @@
 ## 数据结构与算法之美PHP实现
 
 ### 项目运行
-* 依赖composer自动加载，php目录下执行`composer dump-autoload`
+* 依赖composer自动加载，php目录下执行`composer dump-autoload` || `sh buildAutoLoad.sh`
 * 项目代码均在mac&php7环境下跑通
 
 ### 项目实现
-#### 06
+#### 06_linkedlist
 * 单链表php实现
 * 回文判断
-#### 07
+
+#### 07_linkedlist
 * reverse 单链表反转
 * checkCircle 链表中环的检测
 * mergerSortedList 两个有序的链表合并
 * deleteLastKth 删除链表倒数第n个结点
-* findMiddleNode 求链表的中间结点
+* findMiddleNode 求链表的中间结点
+
+#### 08_stack
+* 链栈实现

php/README.md

@@ -6,7 +6,8 @@
  "autoload": {
  "psr-4": {
  "Algo_06\\": "06_linkedlist/",
- "Algo_07\\": "07_linkedlist/"
+ "Algo_07\\": "07_linkedlist/",
+ "Algo_08\\": "08_stack/"
  }
  }
 }