diff --git a/src/main/java/com/dota/Solution.java b/src/main/java/com/dota/Solution.java
index 8b6e5b3..e13d70e 100644
--- a/src/main/java/com/dota/Solution.java
+++ b/src/main/java/com/dota/Solution.java
@@ -1,5 +1,7 @@
 package com.dota;
 
+import java.util.HashMap;
+
 public class Solution {
 	// 1423. 可获得的最大点数
 	public int maxScore(int[] cardPoints, int k) {
@@ -60,4 +62,19 @@ public class Solution {
 
 		return true;
 	}
+}
+
+class Solution2 {
+	public long beautifulSubarrays(int[] nums) {
+		long count = 0;
+		var map = new HashMap<Integer, Integer>();
+		map.put(0, 1);
+		var mask = 0;
+		for (int num : nums) {
+			mask ^= num;
+			count += map.getOrDefault(mask, 0);
+			map.put(mask, map.getOrDefault(mask, 0) + 1);
+		}
+		return count;
+	}
 }
\ No newline at end of file