Merge pull request doganoo#25 from tuqqu/bucket_sort

Author: doganoo

src/Algorithm/Sorting/BucketSort.php

@@ -0,0 +1,75 @@
+<?php
+declare(strict_types=1);
+/**
+ * MIT License
+ *
+ * Copyright (c) 2018 Dogan Ucar
+ *
+ * @author Arthur Kurbidaev <[email protected]>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+namespace doganoo\PHPAlgorithms\Algorithm\Sorting;
+
+use doganoo\PHPAlgorithms\Common\Interfaces\ISortable;
+use function array_fill;
+use function count;
+use function max;
+
+/**
+ * Class BucketSort
+ *
+ * @package doganoo\PHPAlgorithms\Algorithm\Sorting
+ */
+class BucketSort implements ISortable {
+
+    /**
+     * @param array $array
+     * @return array
+     */
+    public function sort(array $array): array {
+        if (empty($array)) {
+            return [];
+        }
+
+        $size    = count($array);
+        $max     = max($array);
+        $buckets = array_fill(0, $size + 1, []);
+
+        foreach ($array as $v) {
+            $bucket = (int) ($size * $v / $max);
+            $buckets[$bucket][] = $v;
+        }
+
+        $insertionSort = new InsertionSort();
+        for ($i = 0; $i < $size; ++$i) {
+            $buckets[$i] = $insertionSort->sort($buckets[$i]);
+        }
+
+        $sorted = [];
+        foreach ($buckets as $bucket) {
+            foreach ($bucket as $v) {
+                $sorted[] = $v;
+            }
+        }
+
+        return $sorted;
+    }
+}

tests/Sorting/SortTest.php

@@ -27,6 +27,7 @@
 namespace doganoo\PHPAlgorithmsTest\Sorting;
 
 use doganoo\PHPAlgorithms\Algorithm\Sorting\BubbleSort;
+use doganoo\PHPAlgorithms\Algorithm\Sorting\BucketSort;
 use doganoo\PHPAlgorithms\Algorithm\Sorting\InsertionSort;
 use doganoo\PHPAlgorithms\Algorithm\Sorting\MergeSort;
 use doganoo\PHPAlgorithms\Algorithm\Sorting\QuickSort;
@@ -149,4 +150,23 @@ public function testRadixSort(): void {
         $this->assertTrue($result === [9]);
     }
 
+    public function testBucketSort(): void {
+        $bucketSort = new BucketSort();
+
+        $result = $bucketSort->sort([12, 40, 9, 55, 1, 13]);
+        $this->assertTrue($result === [1, 9, 12, 13, 40, 55]);
+
+        $result = $bucketSort->sort([5, 21, 7, 23, 19]);
+        $this->assertTrue($result === [5, 7, 19, 21, 23]);
+
+        $result = $bucketSort->sort([201, 3, 0, 98, 97, 53, 132, 89, 32, 35, 32]);
+        $this->assertTrue($result === [0, 3, 32, 32, 35, 53, 89, 97, 98, 132, 201]);
+
+        $result = $bucketSort->sort([]);
+        $this->assertTrue($result === []);
+
+        $result = $bucketSort->sort([1]);
+        $this->assertTrue($result === [1]);
+    }
+
 }