From 2baf830ae575af2d229c5205914e65f7bd7916d3 Mon Sep 17 00:00:00 2001
From: Arunkumar Akilan <arunkumarakilanarun@gmail.com>
Date: Tue, 17 Mar 2026 09:13:15 +0000
Subject: [PATCH 1/5] feat: clean Sprint-2 implementation and tests

---
 Sprint-2/debug/address.js              |  2 +-
 Sprint-2/debug/author.js               | 13 +++++++----
 Sprint-2/debug/recipe.js               | 14 +++++++----
 Sprint-2/implement/contains.js         | 20 +++++++++++++++-
 Sprint-2/implement/contains.test.js    | 32 ++++++++++++++++++++++++++
 Sprint-2/implement/lookup.js           | 10 ++++++--
 Sprint-2/implement/lookup.test.js      |  9 ++++++++
 Sprint-2/implement/querystring.js      |  6 +++--
 Sprint-2/implement/querystring.test.js | 15 ++++++++++++
 Sprint-2/implement/tally.js            | 17 +++++++++++++-
 Sprint-2/implement/tally.test.js       |  9 ++++++++
 Sprint-2/interpret/invert.js           | 11 +++++++--
 Sprint-2/interpret/invert.test.js      | 10 ++++++++
 13 files changed, 151 insertions(+), 17 deletions(-)
 create mode 100644 Sprint-2/interpret/invert.test.js

diff --git a/Sprint-2/debug/address.js b/Sprint-2/debug/address.js
index 940a6af83..fde180d6d 100644
--- a/Sprint-2/debug/address.js
+++ b/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"]}`);
diff --git a/Sprint-2/debug/author.js b/Sprint-2/debug/author.js
index 8c2125977..876962002 100644
--- a/Sprint-2/debug/author.js
+++ b/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);
 }
+
+ 
+
diff --git a/Sprint-2/debug/recipe.js b/Sprint-2/debug/recipe.js
index 6cbdd22cd..15a450935 100644
--- a/Sprint-2/debug/recipe.js
+++ b/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.
\ No newline at end of file
diff --git a/Sprint-2/implement/contains.js b/Sprint-2/implement/contains.js
index cd779308a..8cee952a2 100644
--- a/Sprint-2/implement/contains.js
+++ b/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;
diff --git a/Sprint-2/implement/contains.test.js b/Sprint-2/implement/contains.test.js
index 326bdb1f2..b64015f11 100644
--- a/Sprint-2/implement/contains.test.js
+++ b/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
diff --git a/Sprint-2/implement/lookup.js b/Sprint-2/implement/lookup.js
index a6746e07f..e5f1addc0 100644
--- a/Sprint-2/implement/lookup.js
+++ b/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;
diff --git a/Sprint-2/implement/lookup.test.js b/Sprint-2/implement/lookup.test.js
index 547e06c5a..a1b82e864 100644
--- a/Sprint-2/implement/lookup.test.js
+++ b/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
diff --git a/Sprint-2/implement/querystring.js b/Sprint-2/implement/querystring.js
index 45ec4e5f3..118a27b53 100644
--- a/Sprint-2/implement/querystring.js
+++ b/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;
   }
 
diff --git a/Sprint-2/implement/querystring.test.js b/Sprint-2/implement/querystring.test.js
index 3e218b789..c5681bec4 100644
--- a/Sprint-2/implement/querystring.test.js
+++ b/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"});
+});
diff --git a/Sprint-2/implement/tally.js b/Sprint-2/implement/tally.js
index f47321812..88ff23bb1 100644
--- a/Sprint-2/implement/tally.js
+++ b/Sprint-2/implement/tally.js
@@ -1,3 +1,18 @@
-function tally() {}
+function tally(arr) {
+    const object = {};
+    if(!Array.isArray(arr))
+    {
+        throw new Error("Invalid input: tally expects an array");
+    }
+    if(arr.length === 0)
+    {
+        return object;
+    } 
+    arr.forEach(ele =>{
+        object[ele] =(object[ele] || 0) + 1;
+
+    });
+    return object;
+}
 
 module.exports = tally;
diff --git a/Sprint-2/implement/tally.test.js b/Sprint-2/implement/tally.test.js
index 2ceffa8dd..691b622be 100644
--- a/Sprint-2/implement/tally.test.js
+++ b/Sprint-2/implement/tally.test.js
@@ -13,6 +13,15 @@ const tally = require("./tally.js");
  * tally(['a', 'a', 'a']), target output: { a: 3 }
  * tally(['a', 'a', 'b', 'c']), target output: { a : 2, b: 1, c: 1 }
  */
+test("throws an error when the input is not an array", ()=>{
+    expect(()=>tally("hi")).toThrow();
+});
+test("returns an empty object when the input array is empty",()=>{
+    expect(tally([])).toEqual({});
+});
+test("returns the count of each unique item in the array", ()=>{
+    expect(tally(['a','b','a','c','b','a'])).toEqual({a:3,b:2,c:1})
+});
 
 // Acceptance criteria:
 
diff --git a/Sprint-2/interpret/invert.js b/Sprint-2/interpret/invert.js
index bb353fb1f..0cdc4da5e 100644
--- a/Sprint-2/interpret/invert.js
+++ b/Sprint-2/interpret/invert.js
@@ -9,21 +9,28 @@
 function invert(obj) {
   const invertedObj = {};
 
-  for (const [key, value] of Object.entries(obj)) {
-    invertedObj.key = value;
+  for (const [value, key] of Object.entries(obj)) {
+    invertedObj[key] = value;
   }
 
   return invertedObj;
 }
 
+module.exports = invert;
 // a) What is the current return value when invert is called with { a : 1 }
+//{key:1}
 
 // b) What is the current return value when invert is called with { a: 1, b: 2 }
+//{key:1, key : 2}
 
 // c) What is the target return value when invert is called with {a : 1, b: 2}
+// {'1':'a','2':'b'}
 
 // c) What does Object.entries return? Why is it needed in this program?
+// Object.entries() returns an array of [key, value] pairs from an object. It is used here to loop through the object and access both the key and value in each iteration.
 
 // d) Explain why the current return value is different from the target output
+// The return value is different because the program uses dot notation with a variable instead of bracket notation.
+//  Also, the object needs to be inverted, so the key and value must be swapped when iterating through the entries.
 
 // e) Fix the implementation of invert (and write tests to prove it's fixed!)
diff --git a/Sprint-2/interpret/invert.test.js b/Sprint-2/interpret/invert.test.js
new file mode 100644
index 000000000..a5d0a564b
--- /dev/null
+++ b/Sprint-2/interpret/invert.test.js
@@ -0,0 +1,10 @@
+const invert = require("./invert");
+
+test("returns an object with the key and value swapped when given a single key-value pair", ()=>{
+  expect(invert({a:1})).toEqual({'1':'a'})
+});
+
+test("returns an object with all keys and values swapped for multiple key-value pairs",()=>{
+
+    expect(invert({a:1, b:2})).toEqual({'1':'a','2':'b'})
+});
\ No newline at end of file

From 9c0eeb1b693463a8461ef215c6d18083340ab055 Mon Sep 17 00:00:00 2001
From: Arunkumar Akilan <arunkumarakilanarun@gmail.com>
Date: Sun, 22 Mar 2026 15:52:14 +0000
Subject: [PATCH 2/5] add div for styling

---
 Sprint-3/quote-generator/index.html | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/Sprint-3/quote-generator/index.html b/Sprint-3/quote-generator/index.html
index 30b434bcf..4e2ccc9a2 100644
--- a/Sprint-3/quote-generator/index.html
+++ b/Sprint-3/quote-generator/index.html
@@ -3,13 +3,15 @@
   <head>
     <meta charset="UTF-8" />
     <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-    <title>Title here</title>
-    <script defer src="quotes.js"></script>
+    <title>Quote generator app</title>
+    <link rel="stylesheet" href="style.css" />
   </head>
   <body>
-    <h1>hello there</h1>
-    <p id="quote"></p>
-    <p id="author"></p>
+     <div id="card">
+      <p id="quote"></p>
+     <p id="author"></p>
     <button type="button" id="new-quote">New quote</button>
+    </div>
+     <script src="quotes.js"></script>
   </body>
 </html>

From 333c080c06c2d2cea8534295a1bf13b6314ec49c Mon Sep 17 00:00:00 2001
From: Arunkumar Akilan <arunkumarakilanarun@gmail.com>
Date: Sun, 22 Mar 2026 15:53:35 +0000
Subject: [PATCH 3/5] feat: connect quotes array to DOM and update UI
 dynamically

---
 Sprint-3/quote-generator/quotes.js | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/Sprint-3/quote-generator/quotes.js b/Sprint-3/quote-generator/quotes.js
index 4a4d04b72..e2b65e00d 100644
--- a/Sprint-3/quote-generator/quotes.js
+++ b/Sprint-3/quote-generator/quotes.js
@@ -490,4 +490,19 @@ const quotes = [
   },
 ];
 
-// call pickFromArray with the quotes array to check you get a random quote
+function quoteGenerator()
+{
+
+let randomQuote = pickFromArray(quotes);
+let accessQuote = document.querySelector("#quote");
+accessQuote.textContent = randomQuote.quote;
+let accessAuthor = document.querySelector("#author");
+accessAuthor.textContent = randomQuote.author;
+
+}
+
+quoteGenerator();
+let newQuote = document.querySelector("#new-quote");
+newQuote.addEventListener("click",quoteGenerator)
+
+

From 9197a515b263621dd65c3737ec80b3ffbf6d09bd Mon Sep 17 00:00:00 2001
From: Arunkumar Akilan <arunkumarakilanarun@gmail.com>
Date: Sun, 22 Mar 2026 15:54:32 +0000
Subject: [PATCH 4/5] feat: add layout and styling to match quote generator
 design

---
 Sprint-3/quote-generator/style.css | 37 +++++++++++++++++++++++++++++-
 1 file changed, 36 insertions(+), 1 deletion(-)

diff --git a/Sprint-3/quote-generator/style.css b/Sprint-3/quote-generator/style.css
index 63cedf2d2..941a22aa4 100644
--- a/Sprint-3/quote-generator/style.css
+++ b/Sprint-3/quote-generator/style.css
@@ -1 +1,36 @@
-/** Write your CSS in here **/
+body{
+    background-color:orange;
+    padding: 200px;
+    padding-right: 300px;
+    text-align: center;
+    font-weight: bold;
+    font-family:'Times New Roman', Times, serif;
+    font-size: 20px;
+}
+#quote{
+    color:orange;
+    padding: 20px;
+    font-size: 30px;
+}
+#author{
+    color:orange;
+    text-align: right;
+    font-size: 25px;
+    margin-top: 20px;
+}
+#card{
+    background-color: white;
+    padding: 40px;
+    margin-top: 20px;
+}
+#new-quote{
+    background-color: orange;
+    color: white;
+   display: block;
+   margin-left: auto;   
+   margin-top: 10px;
+   padding: 10px 20px;
+    border: none;
+    font-size: 20px;
+    cursor: pointer;
+}
\ No newline at end of file

From 48423a23642dd32cf2059ccb83f9d37646b2fef1 Mon Sep 17 00:00:00 2001
From: Arunkumar Akilan <arunkumarakilanarun@gmail.com>
Date: Sun, 22 Mar 2026 15:56:05 +0000
Subject: [PATCH 5/5] feat: implement quote generator to pass existing tests

---
 Sprint-3/quote-generator/quotes.test.js | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Sprint-3/quote-generator/quotes.test.js b/Sprint-3/quote-generator/quotes.test.js
index f7b128bf7..a288e3247 100644
--- a/Sprint-3/quote-generator/quotes.test.js
+++ b/Sprint-3/quote-generator/quotes.test.js
@@ -75,3 +75,5 @@ describe("Quote generator", () => {
     expect(authorP).toHaveTextContent("Rosa Parks");
   });
 });
+
+//completed 
\ No newline at end of file