From 42e667009ad034b2733e183840a84006007df225 Mon Sep 17 00:00:00 2001
From: Mahir Shah <mahir.shah@hotmail.com>
Date: Wed, 28 Oct 2026 17:44:08 +0000
Subject: [PATCH 01/23] Fix calculateMedian function, Implement error checking

---
 Sprint-1/fix/median.js | 26 ++++++++++++++++++++++++--
 1 file changed, 24 insertions(+), 2 deletions(-)

diff --git a/Sprint-1/fix/median.js b/Sprint-1/fix/median.js
index 5c5b796e1..7928ccc95 100644
--- a/Sprint-1/fix/median.js
+++ b/Sprint-1/fix/median.js
@@ -6,8 +6,30 @@
 // or contains values that aren't numbers (the function is expected to throw - see the tests).
 
 function calculateMedian(list) {
-  const middleIndex = Math.floor(list.length / 2);
-  const median = list.splice(middleIndex, 1)[0];
+  if (!Array.isArray(list)) {
+    throw new Error("calculateMedian requires an array of numbers");
+  }
+  if (list.length === 0) {
+    throw new Error("calculateMedian requires a non-empty array");
+  }
+
+  if (
+    !list.every(
+      (currentValue) =>
+        typeof currentValue === "number" && !Number.isNaN(currentValue)
+    )
+  ) {
+    throw new Error("calculateMedian requires an array of numbers");
+  }
+
+  const sortedList = list.toSorted((a, b) => a - b);
+  const middleIndex = Math.floor(sortedList.length / 2);
+  let median;
+  if (sortedList.length % 2 === 0) {
+    median = (sortedList[middleIndex - 1] + sortedList[middleIndex]) / 2;
+  } else {
+    median = sortedList[middleIndex];
+  }
   return median;
 }
 

From b20550fb29ded61a3decd817ee18078a9d9e6c41 Mon Sep 17 00:00:00 2001
From: Mahir Shah <mahir.shah@hotmail.com>
Date: Thu, 29 Oct 2026 15:33:34 +0000
Subject: [PATCH 02/23] Implement tests

---
 Sprint-1/implement/max.test.js | 60 ++++++++++++++++++----------------
 1 file changed, 31 insertions(+), 29 deletions(-)

diff --git a/Sprint-1/implement/max.test.js b/Sprint-1/implement/max.test.js
index ff3fbb5e5..0049de42d 100644
--- a/Sprint-1/implement/max.test.js
+++ b/Sprint-1/implement/max.test.js
@@ -12,32 +12,34 @@ We have set things up already so that this file can see your function from the o
 
 const findMax = require("./max.js");
 
-// Given an empty array
-// When passed to the max function
-// Then it should return -Infinity
-// Delete this test.todo and replace it with a test.
-test.todo("given an empty array, returns -Infinity");
-
-// Given an array with one number
-// When passed to the max function
-// Then it should return that number
-
-// Given an array with both positive and negative numbers
-// When passed to the max function
-// Then it should return the largest number overall
-
-// Given an array with just negative numbers
-// When passed to the max function
-// Then it should return the closest one to zero
-
-// Given an array with decimal numbers
-// When passed to the max function
-// Then it should return the largest decimal number
-
-// Given an array containing a value that isn't a number
-// When passed to the max function
-// Then it should throw Error("findMax requires an array of numbers")
-
-// Given something that isn't an array at all, such as "hey", 42 or no argument
-// When passed to the max function
-// Then it should throw Error("findMax requires an array of numbers")
+test("given an empty array, returns -Infinity", () => {
+  expect(findMax([])).toEqual(-Infinity);
+});
+
+test("given an array with one number, returns that number", () => {
+  expect(findMax([10])).toEqual(10);
+});
+
+test("given an array with positive and negative numbers, returns largest number overall", () => {
+  expect(findMax([10, 58, -74, 984, -87, -995, 47])).toEqual(984);
+});
+
+test("given an array with only negative numbers, returns number closest to zero", () => {
+  expect(findMax([-58, -65, -7, -2, -96, -753])).toEqual(-2);
+});
+
+test("given an array with decimal numbers, returns largest decimal number", () => {
+  expect(findMax([10, 9.5, 65.6, 41, 36.8])).toEqual(65.6);
+});
+
+test("given an array with with value that isn't a number, throws error", () => {
+  expect(() => findMax([10, 23, 18, "hello", 89, 2])).toThrow(
+    new Error("findMax requires an array of numbers")
+  );
+});
+
+test("given something that isn't an array, throws error", () => {
+  expect(() =>
+    findMax("Hello").toThrow(new Error("findMax requires an array of numbers"))
+  );
+});

From 6af26a25c4f36dbfb5c4dfa2ccb47c3f6b4072f6 Mon Sep 17 00:00:00 2001
From: Mahir Shah <mahir.shah@hotmail.com>
Date: Thu, 29 Oct 2026 15:41:42 +0000
Subject: [PATCH 03/23] Implement findMax function

---
 Sprint-1/implement/max.js | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/Sprint-1/implement/max.js b/Sprint-1/implement/max.js
index 6dd76378e..886687cf6 100644
--- a/Sprint-1/implement/max.js
+++ b/Sprint-1/implement/max.js
@@ -1,4 +1,24 @@
 function findMax(elements) {
+  if (!Array.isArray(elements)) {
+    throw new Error("findMax requires an array of numbers");
+  }
+
+  if (elements.length === 0) {
+    return -Infinity;
+  }
+
+  if (
+    !elements.every(
+      (currentValue) =>
+        typeof currentValue === "number" && !Number.isNaN(currentValue)
+    )
+  ) {
+    throw new Error("findMax requires an array of numbers");
+  }
+
+  sortedElements = elements.toSorted((a, b) => a - b);
+
+  return sortedElements[sortedElements.length - 1];
 }
 
 module.exports = findMax;

From 7a3e4e510600cb701fa96fd575ec805178303f8a Mon Sep 17 00:00:00 2001
From: Mahir Shah <mahir.shah@hotmail.com>
Date: Thu, 29 Oct 2026 17:14:33 +0000
Subject: [PATCH 04/23] Add tests

---
 Sprint-1/implement/sum.test.js | 53 +++++++++++++++++++---------------
 1 file changed, 29 insertions(+), 24 deletions(-)

diff --git a/Sprint-1/implement/sum.test.js b/Sprint-1/implement/sum.test.js
index a288e0f0a..ea02ff440 100644
--- a/Sprint-1/implement/sum.test.js
+++ b/Sprint-1/implement/sum.test.js
@@ -10,27 +10,32 @@ const sum = require("./sum.js");
 
 // Acceptance Criteria:
 
-// Given an empty array
-// When passed to the sum function
-// Then it should return 0
-test.todo("given an empty array, returns 0")
-
-// Given an array with just one number
-// When passed to the sum function
-// Then it should return that number
-
-// Given an array containing negative numbers
-// When passed to the sum function
-// Then it should still return the correct total sum
-
-// Given an array with decimal/float numbers
-// When passed to the sum function
-// Then it should return the correct total sum
-
-// Given an array containing a value that isn't a number
-// When passed to the sum function
-// Then it should throw Error("sum requires an array of numbers")
-
-// Given something that isn't an array at all, such as "hey", 42 or no argument
-// When passed to the sum function
-// Then it should throw Error("sum requires an array of numbers")
+test("given an empty array, returns 0", () => {
+  expect(sum([])).toEqual(0);
+});
+
+test("given an array with one number, return that number", () => {
+  expect(sum([5])).toEqual(5);
+});
+
+test("given an array with negative numbers, correctly return sum of numbers", () => {
+  expect(sum[(-10, -45, -6, -74)]).toEqual(-135);
+});
+
+test("given an array with decimal numbers, correctly return total sum", () => {
+  expect(sum([12.7, 3.6, 32.48, 8, 32.53])).toEqual(89.31);
+});
+
+test("given an array with some values that aren't numbers, throw an Error", () => {
+  expect(() => {
+    sum([10, 8, 32, "hello", 2, 53, 32]).toThrow(
+      new Error("sum requires an array of numbers")
+    );
+  });
+});
+
+test("given something that isn't an array, throw an Error", () => {
+  expect(() => {
+    sum("hello").toThrow(new Error("sum requires an array of numbers"));
+  });
+});

From 36a519da0d1a3dffad7377b8cc8b706f9f572b2c Mon Sep 17 00:00:00 2001
From: Mahir Shah <mahir.shah@hotmail.com>
Date: Thu, 29 Oct 2026 17:28:19 +0000
Subject: [PATCH 05/23] Fix error tests

---
 Sprint-1/implement/max.test.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Sprint-1/implement/max.test.js b/Sprint-1/implement/max.test.js
index 0049de42d..ec46b1a71 100644
--- a/Sprint-1/implement/max.test.js
+++ b/Sprint-1/implement/max.test.js
@@ -39,7 +39,7 @@ test("given an array with with value that isn't a number, throws error", () => {
 });
 
 test("given something that isn't an array, throws error", () => {
-  expect(() =>
-    findMax("Hello").toThrow(new Error("findMax requires an array of numbers"))
+  expect(() => findMax("Hello")).toThrow(
+    new Error("findMax requires an array of numbers")
   );
 });

From e97ee714124bad8c7dc809faba1001275925bbdc Mon Sep 17 00:00:00 2001
From: Mahir Shah <mahir.shah@hotmail.com>
Date: Thu, 29 Oct 2026 17:31:01 +0000
Subject: [PATCH 06/23] Fix error tests

---
 Sprint-1/implement/sum.test.js | 12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)

diff --git a/Sprint-1/implement/sum.test.js b/Sprint-1/implement/sum.test.js
index ea02ff440..a2cfb3389 100644
--- a/Sprint-1/implement/sum.test.js
+++ b/Sprint-1/implement/sum.test.js
@@ -19,7 +19,7 @@ test("given an array with one number, return that number", () => {
 });
 
 test("given an array with negative numbers, correctly return sum of numbers", () => {
-  expect(sum[(-10, -45, -6, -74)]).toEqual(-135);
+  expect(sum([-10, -45, -6, -74])).toEqual(-135);
 });
 
 test("given an array with decimal numbers, correctly return total sum", () => {
@@ -28,14 +28,12 @@ test("given an array with decimal numbers, correctly return total sum", () => {
 
 test("given an array with some values that aren't numbers, throw an Error", () => {
   expect(() => {
-    sum([10, 8, 32, "hello", 2, 53, 32]).toThrow(
-      new Error("sum requires an array of numbers")
-    );
-  });
+    sum([10, 8, 32, "hello", 2, 53, 32]);
+  }).toThrow(new Error("sum requires an array of numbers"));
 });
 
 test("given something that isn't an array, throw an Error", () => {
   expect(() => {
-    sum("hello").toThrow(new Error("sum requires an array of numbers"));
-  });
+    sum("hello");
+  }).toThrow(new Error("sum requires an array of numbers"));
 });

From 57f287552f9d66b031be94b3a21d264f389c4fed Mon Sep 17 00:00:00 2001
From: Mahir Shah <mahir.shah@hotmail.com>
Date: Thu, 29 Oct 2026 17:42:42 +0000
Subject: [PATCH 07/23] Implement sum function

---
 Sprint-1/implement/sum.js | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/Sprint-1/implement/sum.js b/Sprint-1/implement/sum.js
index 9062aafe3..b7c76e9e3 100644
--- a/Sprint-1/implement/sum.js
+++ b/Sprint-1/implement/sum.js
@@ -1,4 +1,22 @@
 function sum(elements) {
+  if (!Array.isArray(elements)) {
+    throw new Error("sum requires an array of numbers");
+  }
+
+  if (
+    !elements.every(
+      (currentValue) =>
+        typeof currentValue === "number" && !Number.isNaN(currentValue)
+    )
+  ) {
+    throw new Error("sum requires an array of numbers");
+  }
+
+  let total = 0;
+  for (number of elements) {
+    total += number;
+  }
+  return total;
 }
 
 module.exports = sum;

From 1b7b599fef950972bc3041eb6ec56d6b7ab66610 Mon Sep 17 00:00:00 2001
From: Mahir Shah <mahir.shah@hotmail.com>
Date: Thu, 29 Oct 2026 18:10:48 +0000
Subject: [PATCH 08/23] Add tests

---
 Sprint-1/implement/dedupe.test.js | 26 +++++++++++++++-----------
 1 file changed, 15 insertions(+), 11 deletions(-)

diff --git a/Sprint-1/implement/dedupe.test.js b/Sprint-1/implement/dedupe.test.js
index d7c8e3d8e..dec42086e 100644
--- a/Sprint-1/implement/dedupe.test.js
+++ b/Sprint-1/implement/dedupe.test.js
@@ -13,16 +13,20 @@ E.g. dedupe([1, 2, 1]) returns [1, 2]
 
 // Acceptance Criteria:
 
-// Given an empty array
-// When passed to the dedupe function
-// Then it should return an empty array
-test.todo("given an empty array, it returns an empty array");
+test("given an empty array, it returns an empty array", () => {
+  expect(dedupe([])).toEqual([]);
+});
 
-// Given an array with no duplicates
-// When passed to the dedupe function
-// Then it should return a copy of the original array
+test("given an array with no duplicates, should return a copy of the same array", () => {
+  expect(dedupe([1, 5, 9, 23])).toEqual([1, 5, 9, 23]);
+});
 
-// Given an array of strings or numbers
-// When passed to the dedupe function
-// Then it should return a new array with duplicates removed while preserving the 
-// first occurrence of each element from the original array.
+test("given an array with strings or numbers, should return an array with duplicates removed and first occurrence preserved", () => {
+  expect(dedupe([1, 6, 1, "a", 5, 6, "a", "b", "b"])).toEqual([
+    1,
+    6,
+    "a",
+    5,
+    "b",
+  ]);
+});

From 479a30c81f99188996ab5e3bd6158f2b20886b49 Mon Sep 17 00:00:00 2001
From: Mahir Shah <mahir.shah@hotmail.com>
Date: Thu, 29 Oct 2026 18:11:07 +0000
Subject: [PATCH 09/23] Implement dedupe function

---
 Sprint-1/implement/dedupe.js | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/Sprint-1/implement/dedupe.js b/Sprint-1/implement/dedupe.js
index 781e8718a..5631aceef 100644
--- a/Sprint-1/implement/dedupe.js
+++ b/Sprint-1/implement/dedupe.js
@@ -1 +1,12 @@
-function dedupe() {}
+function dedupe(elements) {
+  const dedupedArray = [];
+
+  for (value of elements) {
+    if (!dedupedArray.includes(value)) {
+      dedupedArray.push(value);
+    }
+  }
+  return dedupedArray;
+}
+
+module.exports = dedupe;

From 42bdd8dbff12f76a0e2ae2377d2e53643aafc22c Mon Sep 17 00:00:00 2001
From: Mahir Shah <mahir.shah@hotmail.com>
Date: Fri, 30 Oct 2026 18:36:44 +0000
Subject: [PATCH 10/23] Add tests

---
 Sprint-1/implement/mean.test.js | 64 ++++++++++++++++++---------------
 1 file changed, 35 insertions(+), 29 deletions(-)

diff --git a/Sprint-1/implement/mean.test.js b/Sprint-1/implement/mean.test.js
index 847b88676..3cbf56a44 100644
--- a/Sprint-1/implement/mean.test.js
+++ b/Sprint-1/implement/mean.test.js
@@ -19,32 +19,38 @@ const calculateMean = require("./mean.js");
 
 // Acceptance criteria:
 
-// Given an array of numbers
-// When passed to calculateMean
-// Then it should return their mean
-// Delete this test.todo and replace it with a test.
-test.todo("given [1, 2, 6], returns 3");
-
-// Given an array with a single number
-// When passed to calculateMean
-// Then it should return that number
-
-// Given an array containing negative or decimal numbers
-// When passed to calculateMean
-// Then it should return the correct mean
-
-// Given an empty array
-// When passed to calculateMean
-// Then it should throw Error("calculateMean requires a non-empty array")
-
-// Given a value that isn't an array, e.g. "banana", 42, null or {}
-// When passed to calculateMean
-// Then it should throw Error("calculateMean requires an array of numbers")
-
-// Given no argument at all
-// When passed to calculateMean
-// Then it should throw Error("calculateMean requires an array of numbers")
-
-// Given an array containing a non-number value, e.g. [1, "2", 3]
-// When passed to calculateMean
-// Then it should throw Error("calculateMean requires an array of numbers")
+test("given [1, 2, 6], returns 3", () => {
+  expect(calculateMean([1, 2, 6])).toEqual(3);
+});
+
+test("given array with single number, return that number", () => {
+  expect(calculateMean([5])).toEqual(5);
+});
+
+test("given an array with positive and negative numbers, return the correct mean", () => {
+  expect(calculateMean([5, 8, -2, 7, -9])).toBeCloseTo(1.8);
+});
+
+test("given an empty array, throw an error", () => {
+  expect(() => calculateMean([])).toThrow(
+    "calculateMean requires a non-empty array"
+  );
+});
+
+test("given something that isn't an array, throw an error", () => {
+  expect(() => calculateMean("banana")).toThrow(
+    "calculateMean requires an array of numbers"
+  );
+});
+
+test("given no argument, throw an error", () => {
+  expect(() => calculateMean()).toThrow(
+    "calculateMean requires an array of numbers"
+  );
+});
+
+test("given an array with non-number values, throw an error", () => {
+  expect(() => calculateMean([1, 5, 9, "hello", 4])).toThrow(
+    "calculateMean requires an array of numbers"
+  );
+});

From 03f21b02915d9ffc3e4fefe41f39bcfef2b89cc0 Mon Sep 17 00:00:00 2001
From: Mahir Shah <mahir.shah@hotmail.com>
Date: Fri, 30 Oct 2026 18:48:17 +0000
Subject: [PATCH 11/23] Implement calculateMean function

---
 Sprint-1/implement/mean.js | 28 +++++++++++++++++++++++++++-
 1 file changed, 27 insertions(+), 1 deletion(-)

diff --git a/Sprint-1/implement/mean.js b/Sprint-1/implement/mean.js
index 36909ea1f..039c3507a 100644
--- a/Sprint-1/implement/mean.js
+++ b/Sprint-1/implement/mean.js
@@ -1,3 +1,29 @@
-function calculateMean(list) {}
+function calculateMean(list) {
+  if (!Array.isArray(list)) {
+    throw new Error("calculateMean requires an array of numbers");
+  }
+
+  if (list.length === 0) {
+    throw new Error("calculateMean requires a non-empty array");
+  }
+
+  if (
+    !list.every(
+      (currentValue) =>
+        typeof currentValue === "number" && !Number.isNaN(currentValue)
+    )
+  ) {
+    throw new Error("calculateMean requires an array of numbers");
+  }
+  
+  let total = 0;
+
+  for (number of list) {
+    total += number;
+  }
+  const mean = total / list.length;
+
+  return mean;
+}
 
 module.exports = calculateMean;

From 4d19b025e423f7335cb3d21728927f58af5c81e8 Mon Sep 17 00:00:00 2001
From: Mahir Shah <mahir.shah@hotmail.com>
Date: Fri, 30 Oct 2026 19:09:56 +0000
Subject: [PATCH 12/23] Add tests

---
 Sprint-1/implement/describe-median.test.js | 28 ++++++++++++----------
 1 file changed, 15 insertions(+), 13 deletions(-)

diff --git a/Sprint-1/implement/describe-median.test.js b/Sprint-1/implement/describe-median.test.js
index e7d18a264..e12a9cf7c 100644
--- a/Sprint-1/implement/describe-median.test.js
+++ b/Sprint-1/implement/describe-median.test.js
@@ -17,16 +17,18 @@ const describeMedian = require("./describe-median.js");
 
 // Acceptance criteria:
 
-// Given an array of numbers
-// When passed to describeMedian
-// Then it should return "The median is " followed by the median
-// Delete this test.todo and replace it with a test.
-test.todo('given [1, 2, 3], returns "The median is 2"');
-
-// Given an empty array
-// When passed to describeMedian
-// Then it should return "Could not calculate a median: calculateMedian requires a non-empty array"
-
-// Given something that isn't an array of numbers, e.g. "banana"
-// When passed to describeMedian
-// Then it should return "Could not calculate a median: calculateMedian requires an array of numbers"
+test('given [1, 2, 3], returns "The median is 2"', () => {
+  expect(describeMedian([1, 2, 3])).toEqual("The median is 2");
+});
+
+test('given empty array, returns "Could not calculate a median: calculateMedian requires a non-empty array"', () => {
+  expect(describeMedian([])).toEqual(
+    "Could not calculate a median: calculateMedian requires a non-empty array"
+  );
+});
+
+test('given something that isnt an array of numbers, returns "Could not calculate a median: calculateMedian requires an array of numbers"', () => {
+  expect(describeMedian("banana")).toEqual(
+    "Could not calculate a median: calculateMedian requires an array of numbers"
+  );
+});

From c3a4ffa67000a475cf4cc3a32cba6c86b85cc531 Mon Sep 17 00:00:00 2001
From: Mahir Shah <mahir.shah@hotmail.com>
Date: Fri, 30 Oct 2026 19:10:22 +0000
Subject: [PATCH 13/23] Implement describeMedian function

---
 Sprint-1/implement/describe-median.js | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/Sprint-1/implement/describe-median.js b/Sprint-1/implement/describe-median.js
index 3381cfc0a..551c245f1 100644
--- a/Sprint-1/implement/describe-median.js
+++ b/Sprint-1/implement/describe-median.js
@@ -20,6 +20,18 @@ function calculateMedian(list) {
 }
 
 // Implement this function. See describe-median.test.js for the acceptance criteria.
-function describeMedian(list) {}
+function describeMedian(list) {
+  try {
+    return "The median is " + calculateMedian(list);
+  } catch {
+    if (list.length === 0) {
+      return "Could not calculate a median: calculateMedian requires a non-empty array";
+    }
+
+    if (!Array.isArray(list)) {
+      return "Could not calculate a median: calculateMedian requires an array of numbers";
+    }
+  }
+}
 
 module.exports = describeMedian;

From 8133c48a77519cff160096bcaa0a6b137c2b05a6 Mon Sep 17 00:00:00 2001
From: Mahir Shah <mahir.shah@hotmail.com>
Date: Fri, 30 Oct 2026 19:13:40 +0000
Subject: [PATCH 14/23] Refactor includes function to use for...of loop

---
 Sprint-1/refactor/includes.js | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/Sprint-1/refactor/includes.js b/Sprint-1/refactor/includes.js
index 29dad81f0..916bcae13 100644
--- a/Sprint-1/refactor/includes.js
+++ b/Sprint-1/refactor/includes.js
@@ -1,8 +1,7 @@
 // Refactor the implementation of includes to use a for...of loop
 
 function includes(list, target) {
-  for (let index = 0; index < list.length; index++) {
-    const element = list[index];
+  for (element of list) {
     if (element === target) {
       return true;
     }

From 01acd636551db9be19678190e775b2fe3b10e9e7 Mon Sep 17 00:00:00 2001
From: Mahir Shah <mahir.shah@hotmail.com>
Date: Fri, 6 Nov 2026 18:20:44 +0000
Subject: [PATCH 15/23] Change name of currentValue to value. Add check to see
 if number is finite

---
 Sprint-1/fix/median.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Sprint-1/fix/median.js b/Sprint-1/fix/median.js
index 7928ccc95..cd8cfd690 100644
--- a/Sprint-1/fix/median.js
+++ b/Sprint-1/fix/median.js
@@ -15,8 +15,8 @@ function calculateMedian(list) {
 
   if (
     !list.every(
-      (currentValue) =>
-        typeof currentValue === "number" && !Number.isNaN(currentValue)
+      (value) =>
+        typeof value === "number" && !Number.isNaN(value) && Number.isFinite(value)
     )
   ) {
     throw new Error("calculateMedian requires an array of numbers");

From d166d5f751fbd8724a22563db8d8cc25442c6c59 Mon Sep 17 00:00:00 2001
From: Mahir Shah <mahir.shah@hotmail.com>
Date: Fri, 6 Nov 2026 18:24:13 +0000
Subject: [PATCH 16/23] Made value in for loop const

---
 Sprint-1/implement/dedupe.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Sprint-1/implement/dedupe.js b/Sprint-1/implement/dedupe.js
index 5631aceef..934cb3d08 100644
--- a/Sprint-1/implement/dedupe.js
+++ b/Sprint-1/implement/dedupe.js
@@ -1,7 +1,7 @@
 function dedupe(elements) {
   const dedupedArray = [];
 
-  for (value of elements) {
+  for (const value of elements) {
     if (!dedupedArray.includes(value)) {
       dedupedArray.push(value);
     }

From 3ff7bcaba0f81b0e29e01956c069a34d21ce32f8 Mon Sep 17 00:00:00 2001
From: Mahir Shah <mahir.shah@hotmail.com>
Date: Fri, 6 Nov 2026 18:41:49 +0000
Subject: [PATCH 17/23] Add check that the returned array is a copy and not the
 same array

---
 Sprint-1/implement/dedupe.test.js | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/Sprint-1/implement/dedupe.test.js b/Sprint-1/implement/dedupe.test.js
index dec42086e..2e814b9df 100644
--- a/Sprint-1/implement/dedupe.test.js
+++ b/Sprint-1/implement/dedupe.test.js
@@ -18,7 +18,10 @@ test("given an empty array, it returns an empty array", () => {
 });
 
 test("given an array with no duplicates, should return a copy of the same array", () => {
-  expect(dedupe([1, 5, 9, 23])).toEqual([1, 5, 9, 23]);
+  const testArray = [1, 5, 9, 23];
+  const testResult = dedupe(testArray);
+  expect(testResult).not.toBe(testArray);
+  expect(testResult).toEqual(testArray);
 });
 
 test("given an array with strings or numbers, should return an array with duplicates removed and first occurrence preserved", () => {

From ca33de5b4c79edd28634128310f001cc0820f545 Mon Sep 17 00:00:00 2001
From: Mahir Shah <mahir.shah@hotmail.com>
Date: Fri, 6 Nov 2026 19:22:17 +0000
Subject: [PATCH 18/23] Simplify try catch to use thrown error message

---
 Sprint-1/implement/describe-median.js | 10 ++--------
 1 file changed, 2 insertions(+), 8 deletions(-)

diff --git a/Sprint-1/implement/describe-median.js b/Sprint-1/implement/describe-median.js
index 551c245f1..b24108d88 100644
--- a/Sprint-1/implement/describe-median.js
+++ b/Sprint-1/implement/describe-median.js
@@ -23,14 +23,8 @@ function calculateMedian(list) {
 function describeMedian(list) {
   try {
     return "The median is " + calculateMedian(list);
-  } catch {
-    if (list.length === 0) {
-      return "Could not calculate a median: calculateMedian requires a non-empty array";
-    }
-
-    if (!Array.isArray(list)) {
-      return "Could not calculate a median: calculateMedian requires an array of numbers";
-    }
+  } catch ({ name, message }) {
+    return "Could not calculate a median: " + message;
   }
 }
 

From d4abcdf8f05952b88285d198564e2115906ce572 Mon Sep 17 00:00:00 2001
From: Mahir Shah <mahir.shah@hotmail.com>
Date: Fri, 6 Nov 2026 19:59:28 +0000
Subject: [PATCH 19/23] Use more efficient method to find max element

---
 Sprint-1/implement/max.js | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/Sprint-1/implement/max.js b/Sprint-1/implement/max.js
index 886687cf6..8275216c3 100644
--- a/Sprint-1/implement/max.js
+++ b/Sprint-1/implement/max.js
@@ -16,9 +16,7 @@ function findMax(elements) {
     throw new Error("findMax requires an array of numbers");
   }
 
-  sortedElements = elements.toSorted((a, b) => a - b);
-
-  return sortedElements[sortedElements.length - 1];
+  return Math.max(...elements);
 }
 
 module.exports = findMax;

From 45748c845f5fb3a19eb6623d915df58ac2a2f2d0 Mon Sep 17 00:00:00 2001
From: Mahir Shah <mahir.shah@hotmail.com>
Date: Fri, 6 Nov 2026 20:26:40 +0000
Subject: [PATCH 20/23] Add check for infinite values. Use exported sum
 function from sum.js

---
 Sprint-1/implement/mean.js | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/Sprint-1/implement/mean.js b/Sprint-1/implement/mean.js
index 039c3507a..8a43b02b0 100644
--- a/Sprint-1/implement/mean.js
+++ b/Sprint-1/implement/mean.js
@@ -1,3 +1,5 @@
+const sum = require("./sum.js");
+
 function calculateMean(list) {
   if (!Array.isArray(list)) {
     throw new Error("calculateMean requires an array of numbers");
@@ -9,18 +11,16 @@ function calculateMean(list) {
 
   if (
     !list.every(
-      (currentValue) =>
-        typeof currentValue === "number" && !Number.isNaN(currentValue)
+      (value) =>
+        typeof value === "number" &&
+        !Number.isNaN(value) &&
+        Number.isFinite(value)
     )
   ) {
     throw new Error("calculateMean requires an array of numbers");
   }
-  
-  let total = 0;
 
-  for (number of list) {
-    total += number;
-  }
+  const total = sum(list);
   const mean = total / list.length;
 
   return mean;

From 2d78b202dcfba05a59c64843de12d00e85374b5b Mon Sep 17 00:00:00 2001
From: Mahir Shah <mahir.shah@hotmail.com>
Date: Fri, 6 Nov 2026 20:37:32 +0000
Subject: [PATCH 21/23] Correct decimal sum test to use toBeCloseTo

---
 Sprint-1/implement/sum.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Sprint-1/implement/sum.test.js b/Sprint-1/implement/sum.test.js
index a2cfb3389..64ab8f8d0 100644
--- a/Sprint-1/implement/sum.test.js
+++ b/Sprint-1/implement/sum.test.js
@@ -23,7 +23,7 @@ test("given an array with negative numbers, correctly return sum of numbers", ()
 });
 
 test("given an array with decimal numbers, correctly return total sum", () => {
-  expect(sum([12.7, 3.6, 32.48, 8, 32.53])).toEqual(89.31);
+  expect(sum([12.7, 3.6, 32.48, 8, 32.53])).toBeCloseTo(89.31);
 });
 
 test("given an array with some values that aren't numbers, throw an Error", () => {

From 60a8cf4387fc3f5496f9f6f096027ca4bf6bdae3 Mon Sep 17 00:00:00 2001
From: Mahir Shah <mahir.shah@hotmail.com>
Date: Fri, 6 Nov 2026 20:44:48 +0000
Subject: [PATCH 22/23] Declared loop variable const

---
 Sprint-1/refactor/includes.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Sprint-1/refactor/includes.js b/Sprint-1/refactor/includes.js
index 916bcae13..8c9ae2e66 100644
--- a/Sprint-1/refactor/includes.js
+++ b/Sprint-1/refactor/includes.js
@@ -1,7 +1,7 @@
 // Refactor the implementation of includes to use a for...of loop
 
 function includes(list, target) {
-  for (element of list) {
+  for (const element of list) {
     if (element === target) {
       return true;
     }

From 709eeb822db71e47ac8b0ad50ffe972fcf8878b7 Mon Sep 17 00:00:00 2001
From: Mahir Shah <mahir.shah@hotmail.com>
Date: Sat, 7 Nov 2026 00:31:19 +0000
Subject: [PATCH 23/23] Change currentValue to value. Add check for infinite

---
 Sprint-1/implement/sum.js | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/Sprint-1/implement/sum.js b/Sprint-1/implement/sum.js
index b7c76e9e3..7db276391 100644
--- a/Sprint-1/implement/sum.js
+++ b/Sprint-1/implement/sum.js
@@ -5,8 +5,10 @@ function sum(elements) {
 
   if (
     !elements.every(
-      (currentValue) =>
-        typeof currentValue === "number" && !Number.isNaN(currentValue)
+      (value) =>
+        typeof currentValue === "number" &&
+        !Number.isNaN(value) &&
+        Number.isFinite(value)
     )
   ) {
     throw new Error("sum requires an array of numbers");