From 4e38ab5331b6cf6f53c0477563ee4a8318ac02b8 Mon Sep 17 00:00:00 2001
From: shahayush480 <shahayush480@gmail.com>
Date: Sat, 30 Sep 2023 14:40:27 +0530
Subject: [PATCH 1/3] fix: #758  optimised armstrongNumber code

---
 Maths/ArmstrongNumber.js | 17 +++++++----------
 1 file changed, 7 insertions(+), 10 deletions(-)

diff --git a/Maths/ArmstrongNumber.js b/Maths/ArmstrongNumber.js
index a3ab78299f..8f861d8c15 100644
--- a/Maths/ArmstrongNumber.js
+++ b/Maths/ArmstrongNumber.js
@@ -9,16 +9,13 @@
  */
 
 const armstrongNumber = (num) => {
-  if (num < 0 || typeof num !== 'number') return false
-
-  let newSum = 0
-
-  const numArr = num.toString().split('')
-  numArr.forEach((num) => {
-    newSum += parseInt(num) ** numArr.length
-  })
-
-  return newSum === num
+  if (typeof num !== 'number' || num < 0) return false
+  const numStr = num.toString()
+  const sum = [...numStr].reduce(
+    (acc, digit) => acc + parseInt(digit) ** numStr.length,
+    0
+  )
+  return sum === num
 }
 
 export { armstrongNumber }

From 184ae84413d01387f6808cbab9a2c1a6052aa46e Mon Sep 17 00:00:00 2001
From: shahayush480 <shahayush480@gmail.com>
Date: Sun, 1 Oct 2023 06:03:35 +0530
Subject: [PATCH 2/3] fix:#758 Average Median code optimised

---
 Maths/AverageMedian.js | 16 ++++------------
 1 file changed, 4 insertions(+), 12 deletions(-)

diff --git a/Maths/AverageMedian.js b/Maths/AverageMedian.js
index 3be6c551fc..5a6bb26c56 100644
--- a/Maths/AverageMedian.js
+++ b/Maths/AverageMedian.js
@@ -9,22 +9,14 @@
  */
 
 const averageMedian = (sourceArrayOfNumbers) => {
-  let numbers = [...sourceArrayOfNumbers]
-  let median = 0
+  const numbers = [...sourceArrayOfNumbers].sort(sortNumbers)
   const numLength = numbers.length
-  numbers = numbers.sort(sortNumbers)
 
   if (numLength % 2 === 0) {
-    median = (numbers[numLength / 2 - 1] + numbers[numLength / 2]) / 2
-  } else {
-    median = numbers[(numLength - 1) / 2]
-  }
-
-  return median
+    return (numbers[numLength / 2 - 1] + numbers[numLength / 2]) / 2
+  } else return numbers[Math.floor(numLength / 2)]
 }
 
-const sortNumbers = (num1, num2) => {
-  return num1 - num2
-}
+const sortNumbers = (num1, num2) => num1 - num2
 
 export { averageMedian }

From b8be2f934f883dd0d923d044612145ca698f1c72 Mon Sep 17 00:00:00 2001
From: shahayush480 <shahayush480@gmail.com>
Date: Sun, 1 Oct 2023 18:03:53 +0530
Subject: [PATCH 3/3] feat: TwoSum function added with test cases

---
 Maths/TwoSum.js           | 23 +++++++++++++++++++++++
 Maths/test/TwoSum.test.js | 18 ++++++++++++++++++
 2 files changed, 41 insertions(+)
 create mode 100644 Maths/TwoSum.js
 create mode 100644 Maths/test/TwoSum.test.js

diff --git a/Maths/TwoSum.js b/Maths/TwoSum.js
new file mode 100644
index 0000000000..9b763a60f2
--- /dev/null
+++ b/Maths/TwoSum.js
@@ -0,0 +1,23 @@
+/*
+Given an array of integers, return indices of the two numbers such that they add up to
+a specific target.
+
+You may assume that each input would have exactly one solution, and you may not use the
+same element twice.
+
+Example
+Given nums = [2, 7, 11, 15], target = 9,
+Because nums[0] + nums[1] = 2 + 7 = 9, return [0, 1].
+return [0, 1].
+*/
+
+const TwoSum = (nums, target) => {
+  const numIndicesMap = {}
+  for (let i = 0; i < nums.length; i++) {
+    const complement = target - nums[i]
+    if (complement in numIndicesMap) return [numIndicesMap[complement], i]
+    numIndicesMap[nums[i]] = i
+  }
+  return []
+}
+export { TwoSum }
diff --git a/Maths/test/TwoSum.test.js b/Maths/test/TwoSum.test.js
new file mode 100644
index 0000000000..5d73e24c38
--- /dev/null
+++ b/Maths/test/TwoSum.test.js
@@ -0,0 +1,18 @@
+import { TwoSum } from '../TwoSum.js'
+
+describe('Two Sum', () => {
+  it('Should find the indices of two numbers that add up to the target', () => {
+    expect(TwoSum([2, 7, 11, 15], 9)).toEqual([0, 1])
+    expect(TwoSum([15, 2, 11, 7], 13)).toEqual([1, 2])
+    expect(TwoSum([2, 7, 11, 15], 17)).toEqual([0, 3])
+    expect(TwoSum([7, 15, 11, 2], 18)).toEqual([0, 2])
+    expect(TwoSum([2, 7, 11, 15], 26)).toEqual([2, 3])
+    expect(TwoSum([2, 7, 11, 15], 8)).toEqual([])
+    expect(
+      TwoSum(
+        [...Array(10).keys()].map((i) => 3 * i),
+        19
+      )
+    ).toEqual([])
+  })
+})