Create Sum of Variable Length Subarrays.java

varunu28 · web-flow · commit 72a77c98c7d7 · 2025-01-20T09:55:45.000-08:00
diff --git a/Easy/Sum of Variable Length Subarrays.java b/Easy/Sum of Variable Length Subarrays.java
@@ -0,0 +1,19 @@
+class Solution {
+    public int subarraySum(int[] nums) {
+        int n = nums.length;
+        int[] prefixSum = new int[n];
+        int sum = 0;
+        int result = 0;
+        for (int i = 0; i < n; i++) {
+            sum += nums[i];
+            prefixSum[i] = sum;
+            int start = Math.max(0, i - nums[i]);
+            int subarraySum = prefixSum[i];
+            if (start > 0) {
+                subarraySum -= prefixSum[start - 1];
+            }
+            result += subarraySum;
+        }
+        return result;
+    }
+}
