From 700bb9580f9f10898c61bf4529ec9055f1be9087 Mon Sep 17 00:00:00 2001
From: Gummalla Jashnavi <2400032492@kluniversity.in>
Date: Fri, 7 Nov 2025 17:26:22 +0530
Subject: [PATCH 1/2] Add maxAlternatingSum method in Solution class

Implement maxAlternatingSum method to calculate the maximum alternating sum of an array.
---
 maxAlternatingSum.java | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)
 create mode 100644 maxAlternatingSum.java

diff --git a/maxAlternatingSum.java b/maxAlternatingSum.java
new file mode 100644
index 00000000..b671447f
--- /dev/null
+++ b/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 3ce06cf7c401ac061969d2aa671ad39ed6c130b6 Mon Sep 17 00:00:00 2001
From: Gummalla Jashnavi <2400032492@kluniversity.in>
Date: Fri, 7 Nov 2025 17:38:26 +0530
Subject: [PATCH 2/2] Added algorithm description and complexity comments

---
 maxAlternatingSum.java | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/maxAlternatingSum.java b/maxAlternatingSum.java
index b671447f..3ec20bc0 100644
--- a/maxAlternatingSum.java
+++ b/maxAlternatingSum.java
@@ -1,3 +1,14 @@
+/*
+Algorithm: Max Alternating Sum
+--------------------------------
+Description:
+Calculates the maximum alternating sum of elements in an array.
+The algorithm uses dynamic programming to decide whether to add or subtract
+each number to maximize the total sum.
+
+Time Complexity: O(n)
+Space Complexity: O(1)
+*/
 import java.util.*;
 class Solution {
     public long maxAlternatingSum(int[] nums) {