Birmingham | ITP Jan 2026 | Arunkumar Akilan | Sprint 2 | Data Groups

Sprint-1/fix/median.js

@@ -6,9 +6,41 @@
 // or 'list' has mixed values (the function is expected to sort only numbers).
 
 function calculateMedian(list) {
-  const middleIndex = Math.floor(list.length / 2);
-  const median = list.splice(middleIndex, 1)[0];
-  return median;
+  let newArray = [];
+  if(!Array.isArray(list))
+    {
+      return null;
+    }
+
+  for (const item of list)
+  {
+    if (typeof item === 'number')
+    {
+      newArray.push(item);
+    } 
+
+  }
+  if (newArray.length === 0)
+  {
+    return null;
+  }
+  newArray = newArray.sort((a, b) => a-b);
+  if(newArray.length %2 === 0)
+  {
+     const rightIndex = newArray.length/2
+     const leftIndex = rightIndex - 1;
+     const median = (newArray[rightIndex] + newArray[leftIndex])/2;
+     return median;
+
+  }
+  else{
+
+    const middleIndex = Math.floor(newArray.length/2);
+    return newArray[middleIndex]
+  }
+  //const middleIndex = Math.floor(newArray.length / 2);
+  //const median = list.splice(middleIndex, 1)[0];
+  //return newArray[middleIndex];
 }
 
 module.exports = calculateMedian;

Sprint-1/implement/dedupe.js

@@ -1 +1,17 @@
-function dedupe() {}
+function dedupe(list) {
+  if (list.length=== 0)
+    {
+        return [];
+    }
+     let result = [];
+  for (let item of list)
+  {
+    if(!result.includes(item))
+    {
+        result.push(item);
+    }
+    }
+    return result;
+
+}
+module.exports = dedupe;

Sprint-1/implement/dedupe.test.js

@@ -17,7 +17,18 @@ E.g. dedupe([1, 2, 1]) target output: [1, 2]
 // 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", ()=>{
+    const list = [];
+    expect(dedupe(list)).toEqual([]);
+});
+test
+("array with no duplicate should return copy of original", ()=>{
+    let list = [1,2,4,6,9,8];
+    expect(dedupe(list)).toEqual([1,2,4,6,9,8]);
+});
+test("shoiuld remove the duplicate value and preserving the first occurebce",()=>{
+    expect(dedupe([5, 1, 1, 2, 3, 2, 5, 8])).toEqual([5,1,2,3,8]);
+})
 // Given an array with no duplicates
 // When passed to the dedupe function
 // Then it should return a copy of the original array

Sprint-1/implement/max.js

@@ -1,4 +1,19 @@
 function findMax(elements) {
+    if(elements.length === 0)
+    {
+        return -Infinity;
+    }
+    let max = -Infinity ;
+    for (const item of elements)
+{
+    if (typeof item === 'number')
+    {
+    max =  Math.max(max , item);
+    }
+
+
+}
+  return max;
 }
 
 module.exports = findMax;

Sprint-1/implement/max.test.js

@@ -16,7 +16,34 @@ const findMax = require("./max.js");
 // 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");
+test("given an empty array should return -Infinity", () => {
+  const list = [];
+  expect(findMax(list)).toEqual(-Infinity);
+});
+test("Array with one number should return that number", () => {
+    const list =[7];
+    expect(findMax(list)).toEqual(7);
+});
+test("An array with both positive and negative number should return the largest overall", () =>{
+    const list = [-10, 5, 30, -3];
+    expect(findMax(list)).toEqual(30);
+});
+test("Array with just negative number should return the closest on to zero", () =>{
+    const list = [-10, -3, -20,-7,-4]
+    expect(findMax(list)).toEqual(-3);
+});
+test("An array with decimal number should return largest decimal number", ()=>{
+   const list = [1.2, 3.5, 2.8]
+    expect(findMax(list)).toEqual(3.5);
+});
+test("An array with non-numeric values should return the max and ignore non-numeric", () =>{
+    const list = ['hey', 10, 'hi', 60, 50];
+    expect(findMax(list)).toEqual(60);
+});
+test("An array with non numeric value should  return the least surprising value given how it behaves for all other inputs", ()=> {
+    const list = ['a', 'b', 'hello'];
+    expect(findMax(list)).toEqual(-Infinity);
+})
 
 // Given an array with one number
 // When passed to the max function

Sprint-1/implement/sum.js

@@ -1,4 +1,19 @@
 function sum(elements) {
+    if (elements.length === 0)
+    {
+        return 0;
+    }
+      let total = 0 ;
+    for (const item of elements)
+{
+    if (typeof item === 'number')
+    {
+     total =  total + item;
+    }
+
+
+}
+  return total;
 }
 
 module.exports = sum;

Sprint-1/implement/sum.test.js

@@ -13,7 +13,34 @@ const sum = require("./sum.js");
 // Given an empty array
 // When passed to the sum function
 // Then it should return 0
-test.todo("given an empty array, returns 0")
+test("given an empty array should return -Infinity", () => {
+  const list = [];
+  expect(sum(list)).toEqual(0);
+});
+test("Array with one number should return that number", () => {
+    const list =[7];
+    expect(sum(list)).toEqual(7);
+});
+test("An array with both positive and negative number should return the largest overall", () =>{
+    const list = [-10, 5, 30, -3];
+    expect(sum(list)).toEqual(22);
+});
+test("Array with just negative number should return the closest on to zero", () =>{
+    const list = [-10, -3, -20,-7,-4]
+    expect(sum(list)).toEqual(-44);
+});
+test("An array with decimal number should return largest decimal number", ()=>{
+   const list = [1.2, 3.5, 2.8]
+    expect(sum(list)).toEqual(7.5);
+});
+test("An array with non-numeric values should return the max and ignore non-numeric", () =>{
+    const list = ['hey', 10, 'hi', 60, 50];
+    expect(sum(list)).toEqual(120);
+});
+test("An array with non numeric value should  return the least surprising value given how it behaves for all other inputs", ()=> {
+    const list = ['a', 'b', 'hello'];
+    expect(sum(list)).toEqual(0);
+})
 
 // Given an array with just one number
 // When passed to the sum function

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 (const element of list) {
     if (element === target) {
       return true;
     }

Sprint-2/debug/address.js

@@ -12,4 +12,4 @@ const address = {
   postcode: "XYZ 123",
 };
 
-console.log(`My house number is ${address[0]}`);
+console.log(`My house number is ${address["houseNumber"]}`);

Sprint-2/debug/author.js

@@ -1,5 +1,6 @@
 // Predict and explain first...
-
+// The program throws an error because a for...of loop only works with iterable values like arrays or strings. 
+// The author variable is an object, which is not iterable by default, so JavaScript cannot loop through it.
 // This program attempts to log out all the property values in the object.
 // But it isn't working. Explain why first and then fix the problem
 
@@ -10,7 +11,11 @@ const author = {
   age: 40,
   alive: true,
 };
-
-for (const value of author) {
-  console.log(value);
+const values = Object.values(author);
+for(const item of values)
+{
+    console.log(item);
 }
+
+
+

Sprint-2/debug/recipe.js

@@ -1,5 +1,6 @@
 // Predict and explain first...
-
+//The title and serves values print correctly because the properties are accessed directly using 
+// recipe.title and recipe.serves.
 // This program should log out the title, how many it serves and the ingredients.
 // Each ingredient should be logged on a new line
 // How can you fix it?
@@ -10,6 +11,11 @@ const recipe = {
   ingredients: ["olive oil", "tomatoes", "salt", "pepper"],
 };
 
-console.log(`${recipe.title} serves ${recipe.serves}
-  ingredients:
-${recipe}`);
+console.log(`${recipe.title} serves ${recipe.serves}`);
+for(const ingredients of recipe.ingredients)
+{
+  console.log(`*${ingredients}`)
+}
+
+//The program prints the recipe title and number of servings. 
+// Then it loops through the ingredients array and logs each ingredient on a new line so they are displayed individually instead of printing the whole object.

Sprint-2/implement/contains.js

@@ -1,3 +1,21 @@
-function contains() {}
+function contains(object, propertyName) {
+    if(typeof object !== 'object' || Array.isArray(object) || object=== null)
+    {
+        throw new Error("It is a invalid object")
+    }
+    const newArray = Object.keys(object);
+    for(let item of newArray)
+    {
+       if (item === propertyName)
+        {
+          return true
+       }
+
+
+
+    }
+    return false;
+}
+
 
 module.exports = contains;

Sprint-2/implement/contains.test.js

@@ -11,6 +11,38 @@ E.g. contains({a: 1, b: 2}, 'c') // returns false
 as the object doesn't contains a key of 'c'
 */
 
+test("An empty object should return false",()=>{
+    const object = {};
+    const propertyName = "a";
+    expect(contains(object, propertyName)).toEqual(false);
+});
+
+
+test("returns true when the object contains an existing property name", () => {
+  const object = { a: 1, b: 2, c: 3 };
+  const propertyName = "a";
+  expect(contains(object, propertyName)).toEqual(true);
+});
+test("returns false when the object not contains an existing property name", () => {
+  const object = { a: 1, b: 2, c: 3 };
+  const propertyName = "d";
+  expect(contains(object, propertyName)).toEqual(false);
+});
+test("Should throw an error for an invalid parameters", () => {
+  const object = [1,2,3,4,5,6,7];
+  const propertyName = "a";
+  expect(() => contains(object, propertyName)).toThrow();
+});
+test("Should throw an error for an invalid parameters", () => {
+  const object = null;
+  const propertyName = "a";
+  expect(() => contains(object, propertyName)).toThrow();
+});
+test("Should throw an error for an invalid parameters", () => {
+  const object = "hi";
+  const propertyName = "a";
+  expect(() => contains(object, propertyName)).toThrow();
+});
 // Acceptance criteria:
 
 // Given a contains function

Sprint-2/implement/lookup.js

@@ -1,5 +1,11 @@
-function createLookup() {
-  // implementation here
+function createLookup(countryCurrencyPairs) {
+  const countryCurrencyLookup = {};
+
+  for (let item of countryCurrencyPairs) {
+    const [key, value] = [item[0], item[1]];
+   countryCurrencyLookup[key] = value;
+  }
+  return countryCurrencyLookup;
 }
 
 module.exports = createLookup;

Sprint-2/implement/lookup.test.js

@@ -2,6 +2,15 @@ const createLookup = require("./lookup.js");
 
 test.todo("creates a country currency code lookup for multiple codes");
 
+test("An array of arrays representing country code and currency code should return an object where the keys are country code values are currency code",()=>{
+  const countryCurrencyPairs = [['IND', 'INR'], ['US', 'USD'], ['UK', 'GBR'], ['CA','CAD'] ];
+ expect(createLookup(countryCurrencyPairs)).toEqual({
+   IND: "INR",
+   US: "USD",
+   UK: "GBR",
+   CA: "CAD",
+ });
+})
 /*
 
 Create a lookup object of key value pairs from an array of code pairs

Sprint-2/implement/querystring.js

@@ -5,8 +5,10 @@ function parseQueryString(queryString) {
   }
   const keyValuePairs = queryString.split("&");
 
-  for (const pair of keyValuePairs) {
-    const [key, value] = pair.split("=");
+  for (const item of keyValuePairs) {
+    const pair = item.split("=");
+    const key = pair.shift();
+    const value = pair.join("=");
     queryParams[key] = value;
   }
 

Sprint-2/implement/querystring.test.js

@@ -10,3 +10,18 @@ test("parses querystring values containing =", () => {
     "equation": "x=y+1",
   });
 });
+test("An empty string should return an empty object",()=>{
+  expect(parseQueryString("")).toEqual({});
+});
+test("parses querystring parameters with an empty value",()=>{
+  expect(parseQueryString("name=")).toEqual({name :""});
+});
+test("handles querystring parameters that have no = sign",()=>{
+  expect(parseQueryString("flag")).toEqual({flag:""})
+});
+test("parses querystring values containing multiple = characters",()=>{
+  expect(parseQueryString("token=a=b=c=d")).toEqual({token:"a=b=c=d"});
+});
+test("handles multiple querystring parameters when one value contains =",()=>{
+  expect(parseQueryString("a=1&equation=x=y+1")).toEqual({a:"1", equation:"x=y+1"});
+});