add size method to TeeMap class

Author: walmir-silva

composer.lock

@@ -23,13 +23,15 @@
 class TreeMap implements Map
 {
     private ?TreeMapNode $root = null;
+    private int $size = 0;
 
     public function put(mixed $key, mixed $value): void
     {
         $newNode = new TreeMapNode($key, $value);
         if (null === $this->root) {
             $this->root = $newNode;
             $this->root->setBlack();
+            $this->size++;
         } else {
             $this->insertNode($newNode);
             $this->balanceAfterInsertion($newNode);
@@ -48,10 +50,16 @@ public function remove(mixed $key): bool
             return false;
         }
         $this->deleteNode($node);
+        $this->size--;
 
         return true;
     }
 
+    public function size(): int
+    {
+        return $this->size;
+    }
+
     private function insertNode(TreeMapNode $newNode): void
     {
         $current = $this->root;
@@ -76,6 +84,8 @@ private function insertNode(TreeMapNode $newNode): void
         } else {
             $parent->right = $newNode;
         }
+
+        $this->size++;
         $this->balanceAfterInsertion($newNode);
     }
 

src/Map/TreeMap.php

@@ -0,0 +1,115 @@
+<?php
+
+declare(strict_types=1);
+
+namespace KaririCode\DataStructure\Set;
+
+use KaririCode\Contract\DataStructure\Set;
+use KaririCode\DataStructure\Map\TreeMap;
+
+/**
+ * TreeSet implementation.
+ *
+ * This class implements a set using a TreeMap to store elements. It provides O(log n) time complexity
+ * for add, remove, and contains operations.
+ *
+ * @category  Sets
+ *
+ * @package   KaririCode\DataStructure\Set
+ *
+ * @author    Walmir Silva <walmir.silva@kariricode.org>
+ * @license   MIT
+ *
+ * @see       https://kariricode.org/
+ */
+class TreeSet implements Set
+{
+    private TreeMap $map;
+
+    public function __construct()
+    {
+        $this->map = new TreeMap();
+    }
+
+    /**
+     * Adds an element to the set.
+     *
+     * @param mixed $element The element to add
+     *
+     * @return bool True if the element was added, false if it was already present
+     */
+    public function add(mixed $element): bool
+    {
+        if ($this->map->get($element) !== null) {
+            return false;
+        }
+        $this->map->put($element, true);
+        return true;
+    }
+
+    /**
+     * Removes an element from the set.
+     *
+     * @param mixed $element The element to remove
+     *
+     * @return bool True if the element was removed, false if it was not present
+     */
+    public function remove(mixed $element): bool
+    {
+        return $this->map->remove($element);
+    }
+
+    /**
+     * Checks if the set contains a specific element.
+     *
+     * @param mixed $element The element to check for
+     *
+     * @return bool True if the element is present, false otherwise
+     */
+    public function contains(mixed $element): bool
+    {
+        return $this->map->get($element) !== null;
+    }
+
+    /**
+     * Removes all elements from the set.
+     */
+    public function clear(): void
+    {
+        $this->map = new TreeMap();
+    }
+
+    /**
+     * Returns the number of elements in the set.
+     *
+     * @return int The number of elements in the set
+     */
+    public function size(): int
+    {
+        return $this->map->size();
+    }
+
+    /**
+     * Checks if the set is empty.
+     *
+     * @return bool True if the set is empty, false otherwise
+     */
+    public function isEmpty(): bool
+    {
+        return $this->size() === 0;
+    }
+
+    /**
+     * Returns an array containing all elements in the set.
+     *
+     * @return array The elements in the set
+     */
+    public function toArray(): array
+    {
+        $elements = [];
+        foreach ($this->map as $key => $value) {
+            $elements[] = $key;
+        }
+        return $elements;
+    }
+}

src/Tree/TreeSet.php

@@ -137,6 +137,28 @@ public function testBalancingAfterRemoval(): void
         $this->assertStringContainsString('15:fifteen [RED]', $treeStructure);
     }
 
+    // test size
+    public function testSize(): void
+    {
+        $this->assertSame(0, $this->treeMap->size(), 'Initial size should be 0');
+
+        $this->treeMap->put(1, 'one');
+        $this->assertSame(1, $this->treeMap->size(), 'Size should be 1 after adding one element');
+
+        $this->treeMap->put(2, 'two');
+        $this->assertSame(2, $this->treeMap->size(), 'Size should be 2 after adding another element');
+
+        $this->treeMap->put(1, 'one updated');
+        $this->assertSame(2, $this->treeMap->size(), 'Size should remain 2 after updating an existing element');
+
+        $this->treeMap->remove(1);
+        $this->assertSame(1, $this->treeMap->size(), 'Size should be 1 after removing one element');
+
+        $this->treeMap->remove(2);
+        $this->assertSame(0, $this->treeMap->size(), 'Size should be 0 after removing all elements');
+    }
+
+
     // Test complex operations on the tree.
     public function testComplexOperations(): void
     {