solves

Author: anishLearnsToCode

Diff for: README.txt

@@ -836,7 +836,7 @@
 | 2744 | [Find Maximum Number of String Pairs](https://leetcode.com/problems/find-maximum-number-of-string-pairs)                                                               |                                                                                   [![Java](assets/java.png)](src/FindMaximumNumberOfStringPairs.java)                                                                            |                                                                                                                                   |
 | 2748 | [Number of Beautiful Pairs](https://leetcode.com/problems/number-of-beautiful-pairs)                                                                                   |                                                                                   [![Java](assets/java.png)](src/NumberOfBeautifulPairs.java)                                                                                   |                                                                                                                                   |
 | 2760 | [Longest Even Odd Subarray With Threshold](https://leetcode.com/problems/longest-even-odd-subarray-with-threshold)                                                     |                                                                                   [![Java](assets/java.png)](src/LongestEvenOddSubarrayWithThreshold.java)                                                                                                                                               |                                                                                                                                   |
-| 2765 | [Longest Alternating Subarray](https://leetcode.com/problems/longest-alternating-subarray)                                                                             |                                                                                                                                                                                                                                  |                                                                                                                                   |
+| 2765 | [Longest Alternating Subarray](https://leetcode.com/problems/longest-alternating-subarray)                                                                             |                                                                                   [![Java](assets/java.png)](src/LongestAlternatingSubarray.java)                                                                                                                                               |                                                                                                                                   |
 | 2769 | [Find the Maximum Achievable Number](https://leetcode.com/problems/find-the-maximum-achievable-number)                                                                 |                                                                                                                                                                                                                                  |                                                                                                                                   |
 | 2778 | [Sum of Squares of Special Elements](https://leetcode.com/problems/sum-of-squares-of-special-elements)                                                                 |                                                                                                                                                                                                                                  |                                                                                                                                   |
 | 2784 | [Check if Array is Good](https://leetcode.com/problems/check-if-array-is-good)                                                                                         |                                                                                                                                                                                                                                  |                                                                                                                                   |

Diff for: src/LongestAlternatingSubarray.java

@@ -0,0 +1,15 @@
+// https://leetcode.com/problems/longest-alternating-subarray
+// T: O(N)
+// S: O(1)
+
+public class LongestAlternatingSubarray {
+    public int alternatingSubarray(int[] array) {
+        int maxLength = 0, j = 0;
+        for (int i = 0 ; i < array.length ; i = Math.max(i + 1, j - 1)) {
+            for (j = i + 1 ; j < array.length && array[j] == array[i] + (j - i) % 2 ; j++) {
+                maxLength = Math.max(maxLength, j - i + 1);
+            }
+        }
+        return maxLength > 1 ? maxLength : -1;
+    }
+}