From 928354c3705bad40caeff0e9481f72f0920d5e9c Mon Sep 17 00:00:00 2001
From: Matej Focko <me@mfocko.xyz>
Date: Mon, 20 May 2024 15:47:02 +0200
Subject: [PATCH] =?UTF-8?q?kt:=20add=20=C2=AB1863.=20Sum=20of=20All=20Subs?=
 =?UTF-8?q?et=20XOR=20Totals=C2=BB?=
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Signed-off-by: Matej Focko <me@mfocko.xyz>
---
 kt/sum-of-all-subset-xor-totals.kt | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)
 create mode 100644 kt/sum-of-all-subset-xor-totals.kt

diff --git a/kt/sum-of-all-subset-xor-totals.kt b/kt/sum-of-all-subset-xor-totals.kt
new file mode 100644
index 0000000..1a51ffd
--- /dev/null
+++ b/kt/sum-of-all-subset-xor-totals.kt
@@ -0,0 +1,18 @@
+class Solution {
+    private fun xorSum(
+        nums: IntArray,
+        i: Int,
+        sum: Int,
+    ): Int {
+        if (i == nums.size) {
+            return sum
+        }
+
+        val including = xorSum(nums, i + 1, sum xor nums[i])
+        val excluding = xorSum(nums, i + 1, sum)
+
+        return including + excluding
+    }
+
+    fun subsetXORSum(nums: IntArray): Int = xorSum(nums, 0, 0)
+}