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Michał Żarneckidarwinz
Michał Żarnecki
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darwinz
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implementation of algorithms: 1. compare binary trees, 2. inverse binary tree, 3. reverse linked list
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‎DIRECTORY.md‎

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@@ -28,14 +28,20 @@
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* [Bstree](./DataStructures/BinarySearchTree/BSTree.php)
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* [Duplicatekeyexception](./DataStructures/BinarySearchTree/DuplicateKeyException.php)
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* CompareBinaryTree
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* [CompareBinaryTree](./DataStructures/CompareBinaryTree/CompareBinaryTree.php)
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* [Node](./DataStructures/CompareBinaryTree/Node.php)
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* [CompareBinaryTree](./DataStructures/CompareBinaryTree.php)
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* [BinaryTreeNode](./DataStructures/BinaryTreeNode.php)
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* Disjointsets
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* [Disjointset](./DataStructures/DisjointSets/DisjointSet.php)
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* [Disjointsetnode](./DataStructures/DisjointSets/DisjointSetNode.php)
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* [Doublylinkedlist](./DataStructures/DoublyLinkedList.php)
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* InvertBinaryTree
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* [InvertBinaryTree](./DataStructures/InvertBinaryTree.php)
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* [BinaryTree](./DataStructures/BinaryTree.php)
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* [Node](./DataStructures/Node.php)
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* [Queue](./DataStructures/Queue.php)
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* ReverseLinkedList
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* [ReverseLinkedList.php](DataStructures/ReverseLinkedList.php)
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* [LinkedListItem.php](DataStructures/LinkedListItem.php)
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* Segmenttree
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* [Segmenttree](./DataStructures/SegmentTree/SegmentTree.php)
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* [Segmenttreenode](./DataStructures/SegmentTree/SegmentTreeNode.php)

‎DataStructures/BinaryTree.php‎

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<?php
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class BinaryTree {
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private ?BinaryTree $left = null;
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private ?BinaryTree $right = null;
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private $value;
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public function setLeft(?BinaryTree $left)
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{
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$this->left = $left;
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return $this;
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}
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public function getLeft(): ?BinaryTree
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{
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return $this->left;
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}
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public function setRight(?BinaryTree $right)
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{
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$this->right = $right;
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return $this;
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}
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public function getRight(): ?BinaryTree
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{
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return $this->right;
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}
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public function setValue($value)
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{
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$this->value = $value;
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return $this;
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}
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public function getValue()
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{
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return $this->value;
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}
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}

‎DataStructures/BinaryTreeNode.php‎

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<?php
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namespace DataStructures;
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class BinaryTreeNode
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{
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public function __construct($value, ?BinaryTreeNode $left = null, BinaryTreeNode $right = null)
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{
8+
$this->value = $value;
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$this->left = $left;
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$this->right = $right;
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}
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public $value;
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public ?BinaryTreeNode $left;
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public ?BinaryTreeNode $right;
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}

‎DataStructures/CompareBinaryTree/CompareBinaryTree.php‎ renamed to ‎DataStructures/CompareBinaryTree.php‎

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@@ -1,5 +1,6 @@
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<?php
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namespace DataStructures\CompareBinaryTree;
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namespace DataStructures;
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/**
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* Recurrent comparison of binary trees based on comparison of left and right branches
@@ -11,11 +12,11 @@ class CompareBinaryTree
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{
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/**
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* compare two binary trees
14-
* @param Node|null $a
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* @param Node|null $b
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* @param BinaryTreeNode|null $a
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* @param BinaryTreeNode|null $b
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* @return bool
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*/
18-
public function areTreesEqual(?Node $a, ?Node $b): bool
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public function areTreesEqual(?BinaryTreeNode $a, ?BinaryTreeNode $b): bool
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{
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if (! $a && $b || $a && ! $b) {
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return false;

‎DataStructures/CompareBinaryTree/Node.php‎

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This file was deleted.

‎DataStructures/InvertBinaryTree.php‎

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<?php
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namespace DataStructures;
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use BinaryTree;
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/**
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* Recurrent algorithm to invert binary tree (mirror)
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* (https://medium.com/@kvrware/inverting-binary-tree-b0ff3a5cb0df).
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*
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* @author Michał Żarnecki https://github.com/rzarno
12+
*/
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class InvertBinaryTree
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{
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public function invert(?BinaryTree $b): void
16+
{
17+
if (! $b) {
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return;
19+
}
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$tmp = $b->getLeft();
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$b->setLeft($b->getRight());
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$b->setRight($tmp);
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$this->invert($b->getLeft());
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$this->invert($b->getRight());
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}
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}

‎DataStructures/LinkedListItem.php‎

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<?php
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class LinkedListItem {
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private ?LinkedListItem $next = null;
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private ?LinkedListItem $prev = null;
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private $value;
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public function setNext(?LinkedListItem $next)
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{
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$this->next = $next;
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return $this;
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}
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public function getNext(): ?LinkedListItem
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{
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return $this->next;
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}
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public function setPrev(?LinkedListItem $prev)
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{
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$this->prev = $prev;
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return $this;
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}
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public function getPrev(): ?LinkedListItem
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{
27+
return $this->prev;
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}
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public function setValue($value)
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{
32+
$this->value = $value;
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return $this;
34+
}
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public function getValue()
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{
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return $this->value;
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}
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}

‎DataStructures/ReverseLinkedList.php‎

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<?php
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/**
4+
* Reverse linked list
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* (https://en.wikipedia.org/wiki/Linked_list).
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*
7+
* @author Michał Żarnecki https://github.com/rzarno
8+
*/
9+
class ReverseLinkedList
10+
{
11+
public function reverse(LinkedListItem $item): LinkedListItem
12+
{
13+
$next = $item->getNext();
14+
$item->setNext(null);
15+
while (true) {
16+
$item->setPrev($next);
17+
if (! $next) {
18+
return $item;
19+
}
20+
$nextNext = $next->getNext();
21+
$next->setNext($item);
22+
$item = $next;
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$next = $nextNext;
24+
}
25+
}
26+
}

‎tests/DataStructures/CompareBinaryTreeTest.php‎

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namespace DataStructures;
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require_once __DIR__ . '/../../vendor/autoload.php';
6-
require_once __DIR__ . '/../../DataStructures/CompareBinaryTree/Node.php';
7-
require_once __DIR__ . '/../../DataStructures/CompareBinaryTree/CompareBinaryTree.php';
6+
require_once __DIR__ . '/../../DataStructures/BinaryTreeNode.php';
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require_once __DIR__ . '/../../DataStructures/CompareBinaryTree.php';
88

9-
use DataStructures\CompareBinaryTree\CompareBinaryTree;
10-
use DataStructures\CompareBinaryTree\Node;
119
use PHPUnit\Framework\TestCase;
1210

1311
class CompareBinaryTreeTest extends TestCase
1412
{
1513
public function testBinaryTreesAreEqualWhenAreEqualInReality()
1614
{
17-
$tree1 = new Node(
15+
$tree1 = new BinaryTreeNode(
1816
'A',
19-
new Node(
17+
new BinaryTreeNode(
2018
'B',
21-
new Node(
19+
new BinaryTreeNode(
2220
'D'
2321
),
24-
new Node(
22+
new BinaryTreeNode(
2523
'E',
2624
null,
27-
new Node(
25+
new BinaryTreeNode(
2826
'F'
2927
)
3028
)
3129
),
32-
new Node(
30+
new BinaryTreeNode(
3331
'C',
34-
new Node('G')
32+
new BinaryTreeNode('G')
3533
)
3634
);
3735

@@ -44,43 +42,43 @@ public function testBinaryTreesAreEqualWhenAreEqualInReality()
4442
public function testBinaryTreesAreNotEqualWhenAreNotEqualInReality()
4543
{
4644

47-
$tree1 = new Node(
45+
$tree1 = new BinaryTreeNode(
4846
'A',
49-
new Node(
47+
new BinaryTreeNode(
5048
'B',
51-
new Node(
49+
new BinaryTreeNode(
5250
'F'
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),
54-
new Node(
52+
new BinaryTreeNode(
5553
'E',
5654
null,
57-
new Node(
55+
new BinaryTreeNode(
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'D'
5957
)
6058
)
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),
62-
new Node(
60+
new BinaryTreeNode(
6361
'C',
64-
new Node('G')
62+
new BinaryTreeNode('G')
6563
)
6664
);
6765

68-
$tree2 = new Node(
66+
$tree2 = new BinaryTreeNode(
6967
'A',
70-
new Node(
68+
new BinaryTreeNode(
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'B',
72-
new Node(
70+
new BinaryTreeNode(
7371
'F'
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),
75-
new Node(
73+
new BinaryTreeNode(
7674
'E',
7775
null,
78-
new Node(
76+
new BinaryTreeNode(
7977
'D'
8078
)
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)
8280
),
83-
new Node(
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new BinaryTreeNode(
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'C'
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)
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);

‎tests/DataStructures/InvertBinaryTreeTest.php‎

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<?php
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3+
namespace DataStructures;
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require_once __DIR__ . '/../../vendor/autoload.php';
6+
require_once __DIR__ . '/../../DataStructures/BinaryTree.php';
7+
require_once __DIR__ . '/../../DataStructures/InvertBinaryTree.php';
8+
9+
use BinaryTree;
10+
use PHPUnit\Framework\TestCase;
11+
12+
class InvertBinaryTreeTest extends TestCase
13+
{
14+
public function testInvertBinaryTree()
15+
{
16+
$b = (new BinaryTree())->setValue(1);
17+
$bl = (new BinaryTree())->setValue(3);
18+
$b->setLeft($bl);
19+
$br = (new BinaryTree())->setValue(2);
20+
$b->setRight($br);
21+
$br->setLeft((new BinaryTree())->setValue(4));
22+
$br->setRight((new BinaryTree())->setValue(5));
23+
24+
$expected = (new BinaryTree())->setValue(1);
25+
$expectedBr = (new BinaryTree())->setValue(3);
26+
$expected->setRight($expectedBr);
27+
$expectedBl = (new BinaryTree())->setValue(2);
28+
$expected->setLeft($expectedBl);
29+
$expectedBl->setRight((new BinaryTree())->setValue(4));
30+
$expectedBl->setLeft((new BinaryTree())->setValue(5));
31+
32+
(new InvertBinaryTree())->invert($b);
33+
34+
$this->assertEquals($expected, $b);
35+
}
36+
}

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