From e6f1a47b7790624d8081b64103fcea3c4f9c735a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ozan=20=C3=96zayranci?=
 <38402864+oozan@users.noreply.github.com>
Date: Tue, 21 Jul 2026 19:05:27 +0300
Subject: [PATCH 1/2] perf: optimize aliquot sum calculation

---
 maths/aliquot_sum.ts | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/maths/aliquot_sum.ts b/maths/aliquot_sum.ts
index 0cfeb1db..47a26cbb 100644
--- a/maths/aliquot_sum.ts
+++ b/maths/aliquot_sum.ts
@@ -17,10 +17,17 @@ export const aliquotSum = (num: number): number => {
   if (num < 0) throw new TypeError('Input cannot be negative')
   if (!Number.isInteger(num)) throw new TypeError('Input cannot be a decimal')
 
-  let sum = 0
+  if (num <= 1) return 0
 
-  for (let i = 1; i <= num / 2; i++) {
-    if (num % i === 0) sum += i
+  let sum = 1
+
+  for (let divisor = 2; divisor <= num / divisor; divisor++) {
+    if (num % divisor === 0) {
+      sum += divisor
+
+      const pairedDivisor = num / divisor
+      if (pairedDivisor !== divisor) sum += pairedDivisor
+    }
   }
 
   return sum

From 81d6a48bfd0ad6f252184fb41befff3e8e36dadf Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ozan=20=C3=96zayranci?=
 <38402864+oozan@users.noreply.github.com>
Date: Tue, 21 Jul 2026 19:05:28 +0300
Subject: [PATCH 2/2] test: cover aliquot sum edge cases

---
 maths/test/aliquot_sum.test.ts | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/maths/test/aliquot_sum.test.ts b/maths/test/aliquot_sum.test.ts
index 258b5f69..09b046bf 100644
--- a/maths/test/aliquot_sum.test.ts
+++ b/maths/test/aliquot_sum.test.ts
@@ -1,6 +1,9 @@
 import { aliquotSum } from '../aliquot_sum'
 
 test.each([
+  [0, 0],
+  [1, 0],
+  [2, 1],
   [15, 9],
   [18, 21],
   [28, 28],