Reverse Linked List II

Author: RamyHakam

LinkedList/ReverseLinkedListII.php

@@ -0,0 +1,39 @@
+<?php
+
+namespace Hakam\LeetCodePhp\LinkedList;
+/**
+ * LeetCode Problem Link : https://leetcode.com/problems/reverse-linked-list-ii
+ */
+class ReverseLinkedListII
+{
+    /**
+     * @param ListNode $head
+     * @param Integer $left
+     * @param Integer $right
+     * @return ListNode
+     */
+  public  function reverseBetween(ListNode $head, int $left, int $right): ListNode
+    {
+        $sentinel = new ListNode(0, $head);
+        $p1 = $sentinel;
+
+        for ($i = 0; $i < $left - 1; $i++) {
+            $p1 = $p1->next;
+        }
+
+        $p2 = $p1->next;
+        $p3 = $p2;
+        $reverted = null;
+
+        for ($i = 0; $i <= ($right - $left); $i++) {
+            $tmp = $p2->next;
+            $p2->next = $reverted;
+            $reverted = $p2;
+            $p2 = $tmp;
+        }
+
+        $p1->next = $reverted;
+        $p3->next = $p2;
+        return $sentinel->next;
+    }
+}

Tests/Helper/InputFiles/ReverseLinkedListIITest.json

@@ -0,0 +1,10 @@
+{
+  "testCase1": {
+    "expectedResult":[1,4,3,2,5],
+    "input": [[1,2,3,4,5],2,4]
+  },
+  "testCase2": {
+    "expectedResult":[5],
+    "input": [[5],1,1]
+  }
+}

Tests/LinkedList/ReverseLinkedListIITest.php

@@ -0,0 +1,26 @@
+<?php
+
+namespace Hakam\LeetCodePhp\Tests\LinkedList;
+
+use Hakam\LeetCodePhp\LinkedList\ReverseLinkedListII;
+use Hakam\LeetCodePhp\Tests\Helper\LinkedListHelperTrait;
+use Hakam\LeetCodePhp\Tests\Helper\MainTest;
+
+/**
+ * @covers \Hakam\LeetCodePhp\LinkedList\ReverseLinkedListII
+ */
+class ReverseLinkedListIITest extends MainTest
+{
+    use LinkedListHelperTrait;
+
+    /**
+     * @dataProvider provideData
+     */
+    public function testWithDataList($expectedResult, $inputData): void
+    {
+        $reversList = new ReverseLinkedListII();
+        $list = $this->convertFromArray($inputData[0]);
+        self::assertEmpty(array_diff($expectedResult,
+            $this->convertToArray($reversList->reverseBetween($list,$inputData[1],$inputData[2]))));
+    }
+}