php二叉樹遍歷代碼大全

字號(hào):

    無論是身處學(xué)校還是步入社會(huì),大家都嘗試過寫作吧,借助寫作也可以提高我們的語言組織能力。范文怎么寫才能發(fā)揮它最大的作用呢?下面是小編幫大家整理的優(yōu)質(zhì)范文,僅供參考,大家一起來看看吧。
    php二叉樹遍歷代碼篇一
    本文主要介紹了php實(shí)現(xiàn)的二叉樹遍歷算法,結(jié)合具體實(shí)例形式分析了php針對(duì)二叉樹的常用前序、中序及后序遍歷算法實(shí)現(xiàn)技巧,需要的朋友可以參考一下!想了解更多相關(guān)信息請(qǐng)持續(xù)關(guān)注我們應(yīng)屆畢業(yè)生考試網(wǎng)!
    <?php
    class node {
    public $value;
    public $child_left;
    public $child_right;
    }
    final class ergodic {
    //前序遍歷:先訪問根節(jié)點(diǎn),再遍歷左子樹,最后遍歷右子樹;并且在遍歷左右子樹時(shí),仍需先遍歷根節(jié)點(diǎn),然后訪問左子樹,最后遍歷右子樹
    public static function preorder($root){
    $stack = array();
    array_push($stack, $root);
    while(!empty($stack)){
    $center_node = array_pop($stack);
    echo $center_node->value . ' ';
    //先把右子樹節(jié)點(diǎn)入棧,以確保左子樹節(jié)點(diǎn)先出棧
    if($center_node->child_right != null) array_push($stack, $center_node->child_right);
    if($center_node->child_left != null) array_push($stack, $center_node->child_left);
    }
    }
    //中序遍歷:先遍歷左子樹、然后訪問根節(jié)點(diǎn),最后遍歷右子樹;并且在遍歷左右子樹的時(shí)候。仍然是先遍歷左子樹,然后訪問根節(jié)點(diǎn),最后遍歷右子樹
    public static function midorder($root){
    $stack = array();
    $center_node = $root;
    while (!empty($stack) || $center_node != null) {
    while ($center_node != null) {
    array_push($stack, $center_node);
    $center_node = $center_node->child_left;
    }
    $center_node = array_pop($stack);
    echo $center_node->value . ' ';
    $center_node = $center_node->child_right;
    }
    }
    //后序遍歷:先遍歷左子樹,然后遍歷右子樹,最后訪問根節(jié)點(diǎn);同樣,在遍歷左右子樹的時(shí)候同樣要先遍歷左子樹,然后遍歷右子樹,最后訪問根節(jié)點(diǎn)
    public static function endorder($root){
    $push_stack = array();
    $visit_stack = array();
    array_push($push_stack, $root);
    while (!empty($push_stack)) {
    $center_node = array_pop($push_stack);
    array_push($visit_stack, $center_node);
    //左子樹節(jié)點(diǎn)先入$pushstack的棧,確保在$visitstack中先出棧
    if ($center_node->child_left != null) array_push($push_stack, $center_node->child_left);
    if ($center_node->child_right != null) array_push($push_stack, $center_node->child_right);
    }
    while (!empty($visit_stack)) {
    $center_node = array_pop($visit_stack);
    echo $center_node->value . ' ';
    }
    }
    }
    //創(chuàng)建二叉樹
    $a = new node();
    $b = new node();
    $c = new node();
    $d = new node();
    $e = new node();
    $f = new node();
    $g = new node();
    $h = new node();
    $i = new node();
    $a->value = 'a';
    $b->value = 'b';
    $c->value = 'c';
    $d->value = 'd';
    $e->value = 'e';
    $f->value = 'f';
    $g->value = 'g';
    $h->value = 'h';
    $i->value = 'i';
    $a->child_left = $b;
    $a->child_right = $c;
    $b->child_left = $d;
    $b->child_right = $g;
    $c->child_left = $e;
    $c->child_right = $f;
    $d->child_left = $h;
    $d->child_right = $i;
    //前序遍歷
    ergodic::preorder($a); //結(jié)果是:a b d h i g c e f
    echo '<br/>';
    //中序遍歷
    ergodic::midorder($a); //結(jié)果是: h d i b g a e c f
    echo '<br/>';
    //后序遍歷
    ergodic::endorder($a); //結(jié)果是: h i d g b e f c a
    s("content_relate");
    【php如何實(shí)現(xiàn)的二叉樹遍歷(示例)】相關(guān)文章:
    php如何實(shí)現(xiàn)快速排序
    09-07
    如何用php實(shí)現(xiàn)找回密碼
    09-21
    php如何實(shí)現(xiàn)驗(yàn)證碼
    09-07
    php弱類型變量是如何實(shí)現(xiàn)的
    09-03
    php代碼如何實(shí)現(xiàn)命令行執(zhí)行
    09-30
    c++如何實(shí)現(xiàn)二叉樹葉子節(jié)點(diǎn)個(gè)數(shù)計(jì)算
    10-04
    php多線程的實(shí)現(xiàn)方法
    09-12
    php如何通過會(huì)話控制實(shí)現(xiàn)身份驗(yàn)證
    09-22
    php如何實(shí)現(xiàn)注冊(cè)后郵箱驗(yàn)證和帳號(hào)激活
    09-15