Added Kadane's Algorithm (Maximum Subarray Sum)

Author: Mansi5164

src/main/java/com/thealgorithms/dynamicprogramming/KadanesAlgorithm.java

@@ -0,0 +1,16 @@
+package com.thealgorithms.dynamicprogramming;
+
+public class KadanesAlgorithm {
+    public static int maxSubArraySum(int[] nums) {
+        if (nums == null || nums.length == 0) {
+            throw new IllegalArgumentException("Input array cannot be null or empty");
+        }
+        int maxSoFar = nums[0];
+        int currentMax = nums[0];
+        for (int i = 1; i < nums.length; i++) {
+            currentMax = Math.max(nums[i], currentMax + nums[i]);
+            maxSoFar = Math.max(maxSoFar, currentMax);
+        }
+        return maxSoFar;
+    }
+}

src/test/java/com/thealgorithms/dynamicprogramming/TestKadane.java

@@ -0,0 +1,12 @@
+package com.thealgorithms.dynamicprogramming;
+
+public class TestKadane {
+    public static void main(String[] args) {
+        int[] arr = {-2, 1, -3, 4, -1, 2, 1, -5, 4};
+        System.out.println(maxSubArraySum(arr)); // Expected: 6
+    }
+
+    private static int maxSubArraySum(int[] nums) {
+        return KadanesAlgorithm.maxSubArraySum(nums);
+    }
+}