From ff6602c5ae08bd00b3fad14a6014a21259e7ef77 Mon Sep 17 00:00:00 2001
From: Gummalla Jashnavi <2400032492@kluniversity.in>
Date: Fri, 21 Nov 2025 00:38:08 +0530
Subject: [PATCH 1/2] Add MaxAlternatingSum algorithm implementation

---
 .../devutils/MaxAlternatingSum.java           | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)
 create mode 100644 src/main/java/com/thealgorithms/devutils/MaxAlternatingSum.java

diff --git a/src/main/java/com/thealgorithms/devutils/MaxAlternatingSum.java b/src/main/java/com/thealgorithms/devutils/MaxAlternatingSum.java
new file mode 100644
index 000000000000..b671447fa375
--- /dev/null
+++ b/src/main/java/com/thealgorithms/devutils/MaxAlternatingSum.java
@@ -0,0 +1,19 @@
+import java.util.*;
+class Solution {
+    public long maxAlternatingSum(int[] nums) {
+        int n=nums.length;
+        long[] a=new long[n];
+        for(int i=0;i<n;i++){
+            a[i]=(long)nums[i]*nums[i];
+        }
+        Arrays.sort(a);
+        int k=(n+1)/2;
+        long total=0;
+        for(long v : a) total+=v;
+        long sum=0;
+        for(int i=n-1;i>=n-k;i--){
+            sum +=a[i];
+        }
+        return 2*sum-total;
+    }
+}

From 6d4dfbef11841543b0f16adfa9fa3b7281ecf5ca Mon Sep 17 00:00:00 2001
From: Gummalla Jashnavi <2400032492@kluniversity.in>
Date: Fri, 21 Nov 2025 00:39:49 +0530
Subject: [PATCH 2/2] Add MaxAlternatingSum algorithm implementation

Refactored maxAlternatingSum method to use squared values and improved variable naming.
---
 .../devutils/MaxAlternatingSum.java           | 52 ++++++++++++++-----
 1 file changed, 38 insertions(+), 14 deletions(-)

diff --git a/src/main/java/com/thealgorithms/devutils/MaxAlternatingSum.java b/src/main/java/com/thealgorithms/devutils/MaxAlternatingSum.java
index b671447fa375..dbb9bc4b88dc 100644
--- a/src/main/java/com/thealgorithms/devutils/MaxAlternatingSum.java
+++ b/src/main/java/com/thealgorithms/devutils/MaxAlternatingSum.java
@@ -1,19 +1,43 @@
-import java.util.*;
-class Solution {
+package com.thealgorithms.devutils;
+
+import java.util.Arrays;
+
+/**
+ * Computes the maximum alternating sum based on the squared values of the input array.
+ *
+ * Steps:
+ * 1. Convert nums[i] to nums[i]^2
+ * 2. Sort the squared array
+ * 3. Select the largest (n + 1) / 2 elements
+ * 4. Use formula: result = 2 * sum(selected) - totalSum
+ *
+ * Time Complexity: O(n log n)
+ * Space Complexity: O(n)
+ */
+public class MaxAlternatingSum {
+
     public long maxAlternatingSum(int[] nums) {
-        int n=nums.length;
-        long[] a=new long[n];
-        for(int i=0;i<n;i++){
-            a[i]=(long)nums[i]*nums[i];
+        int n = nums.length;
+        long[] squared = new long[n];
+
+        for (int i = 0; i < n; i++) {
+            squared[i] = (long) nums[i] * nums[i];
         }
-        Arrays.sort(a);
-        int k=(n+1)/2;
-        long total=0;
-        for(long v : a) total+=v;
-        long sum=0;
-        for(int i=n-1;i>=n-k;i--){
-            sum +=a[i];
+
+        Arrays.sort(squared);
+
+        int k = (n + 1) / 2;
+
+        long total = 0;
+        for (long v : squared) {
+            total += v;
         }
-        return 2*sum-total;
+
+        long maxHalf = 0;
+        for (int i = n - 1; i >= n - k; i--) {
+            maxHalf += squared[i];
+        }
+
+        return 2 * maxHalf - total;
     }
 }