From 5afdf823b3620b0b54655feb2299b3a9583a9af2 Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Thu, 26 Feb 2026 12:16:51 +0000
Subject: [PATCH 01/32]  correct access to houseNumber in address object

---
 Sprint-2/debug/address.js | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/Sprint-2/debug/address.js b/Sprint-2/debug/address.js
index 940a6af83..1b79994c6 100644
--- a/Sprint-2/debug/address.js
+++ b/Sprint-2/debug/address.js
@@ -1,4 +1,6 @@
 // Predict and explain first...
+// it will print : My house number is undefined
+//objects aren't indexed
 
 // This code should log out the houseNumber from the address object
 // but it isn't working...
@@ -12,4 +14,4 @@ const address = {
   postcode: "XYZ 123",
 };
 
-console.log(`My house number is ${address[0]}`);
+console.log(`My house number is ${address.houseNumber}`);

From 8a0b3af6d285bdc99ca069146ca9eadde72d4bde Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Thu, 26 Feb 2026 12:27:14 +0000
Subject: [PATCH 02/32] correct iteration method to log author properties

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

diff --git a/Sprint-2/debug/author.js b/Sprint-2/debug/author.js
index 8c2125977..27c25c3a6 100644
--- a/Sprint-2/debug/author.js
+++ b/Sprint-2/debug/author.js
@@ -1,4 +1,6 @@
 // Predict and explain first...
+//for...of works only on iterable data types
+// we will get an error
 
 // 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
@@ -11,6 +13,6 @@ const author = {
   alive: true,
 };
 
-for (const value of author) {
-  console.log(value);
+for (const key in author) {
+  console.log(author[key]);
 }

From f8203998d50689d5027e63d70be81e5a8bb8ce5a Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Thu, 26 Feb 2026 12:41:14 +0000
Subject: [PATCH 03/32] update recipe logging to display ingredients on new
 lines

---
 Sprint-2/debug/recipe.js | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/Sprint-2/debug/recipe.js b/Sprint-2/debug/recipe.js
index 6cbdd22cd..b0244844f 100644
--- a/Sprint-2/debug/recipe.js
+++ b/Sprint-2/debug/recipe.js
@@ -1,4 +1,8 @@
 // Predict and explain first...
+//this will log: bruschetta serves 2 ingredients: title: "bruschetta",
+  // serves: 2,
+  // ingredients: ["olive oil", "tomatoes", "salt", "pepper"],
+//instead of the ingredients it prints the whole object again , also there is no \n 
 
 // This program should log out the title, how many it serves and the ingredients.
 // Each ingredient should be logged on a new line
@@ -10,6 +14,10 @@ const recipe = {
   ingredients: ["olive oil", "tomatoes", "salt", "pepper"],
 };
 
-console.log(`${recipe.title} serves ${recipe.serves}
-  ingredients:
-${recipe}`);
+let ingredients=[]
+ for(let ingredient of recipe.ingredients){
+  ingredients.push(ingredient)
+ }
+  console.log(
+  `${recipe.title} serves ${recipe.serves} ingredients:\n${ingredients.join("\n")}`)
+

From 6e37fe5c4445dc075dc8911e0e408fa7b742a08a Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Thu, 26 Feb 2026 14:39:12 +0000
Subject: [PATCH 04/32] implement contains function and add tests for empty and
 existing properties

---
 Sprint-2/implement/contains.js      | 13 ++++++++++++-
 Sprint-2/implement/contains.test.js | 10 +++++++++-
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/Sprint-2/implement/contains.js b/Sprint-2/implement/contains.js
index cd779308a..2afb09458 100644
--- a/Sprint-2/implement/contains.js
+++ b/Sprint-2/implement/contains.js
@@ -1,3 +1,14 @@
-function contains() {}
+function contains(obj,propertyName) {
+  
+    
+if(Object.keys(obj).length!==0){
+    return true
+}
+if (Object.keys(obj) === propertyName) {
+  return true;
+}
+return false
+}
+console.log(contains({a:"t",k:5},"k"));
 
 module.exports = contains;
diff --git a/Sprint-2/implement/contains.test.js b/Sprint-2/implement/contains.test.js
index 326bdb1f2..f6a687e40 100644
--- a/Sprint-2/implement/contains.test.js
+++ b/Sprint-2/implement/contains.test.js
@@ -20,11 +20,19 @@ as the object doesn't contains a key of 'c'
 // Given an empty object
 // When passed to contains
 // Then it should return false
-test.todo("contains on empty object returns false");
+test("contains on empty object and propertyName='k' returns false", () => {
+  expect(contains({}, "k")).toEqual(false);
+});
 
 // Given an object with properties
 // When passed to contains with an existing property name
 // Then it should return true
+test(
+  "when contains is called with an object and an existing property name as arguments,it returns true ",()=>{
+    expect(contains({a:9},"a")).toEqual(true)
+  }
+);
+
 
 // Given an object with properties
 // When passed to contains with a non-existent property name

From 4fd1b2de973ced4481678b64454879925e83bbc5 Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Thu, 26 Feb 2026 14:40:57 +0000
Subject: [PATCH 05/32] fix contains function to correctly check for property
 existence in object

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

diff --git a/Sprint-2/implement/contains.js b/Sprint-2/implement/contains.js
index 2afb09458..51b50e700 100644
--- a/Sprint-2/implement/contains.js
+++ b/Sprint-2/implement/contains.js
@@ -4,7 +4,7 @@ function contains(obj,propertyName) {
 if(Object.keys(obj).length!==0){
     return true
 }
-if (Object.keys(obj) === propertyName) {
+if (Object.keys(obj).includes(propertyName)) {
   return true;
 }
 return false

From 400346f7b3dc3d0d305bfb417adc61a3aa3ba8c8 Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Thu, 26 Feb 2026 14:43:28 +0000
Subject: [PATCH 06/32] fix contains function to correctly return false for
 empty objects

---
 Sprint-2/implement/contains.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/Sprint-2/implement/contains.js b/Sprint-2/implement/contains.js
index 51b50e700..bb215941d 100644
--- a/Sprint-2/implement/contains.js
+++ b/Sprint-2/implement/contains.js
@@ -1,14 +1,14 @@
 function contains(obj,propertyName) {
   
     
-if(Object.keys(obj).length!==0){
-    return true
+if(Object.keys(obj).length===0){
+    return false
 }
 if (Object.keys(obj).includes(propertyName)) {
   return true;
 }
 return false
 }
-console.log(contains({a:"t",k:5},"k"));
+console.log(contains({a:"t",k:5},"o"));
 
 module.exports = contains;

From 6e91927bf496c38d87c678a2c4c9b25fdf4ab872 Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Thu, 26 Feb 2026 14:45:57 +0000
Subject: [PATCH 07/32] add test case for contains function with non-existing
 property name

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

diff --git a/Sprint-2/implement/contains.test.js b/Sprint-2/implement/contains.test.js
index f6a687e40..59943cc1a 100644
--- a/Sprint-2/implement/contains.test.js
+++ b/Sprint-2/implement/contains.test.js
@@ -37,6 +37,10 @@ test(
 // Given an object with properties
 // When passed to contains with a non-existent property name
 // Then it should return false
+test("when contains is called with an object and a non-existing property name as arguments,it returns false ", () => {
+  expect(contains({ a: 9,color:"pink",day:"Sunday" }, "John")).toEqual(false);
+});
+
 
 // Given invalid parameters like an array
 // When passed to contains

From 06b37671ca689ba4dd5900921cbbc97cbdf8f305 Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Thu, 26 Feb 2026 14:58:28 +0000
Subject: [PATCH 08/32] add error handling test for contains function with
 invalid object type

---
 Sprint-2/implement/contains.js      | 23 ++++++++++++-----------
 Sprint-2/implement/contains.test.js |  4 ++++
 2 files changed, 16 insertions(+), 11 deletions(-)

diff --git a/Sprint-2/implement/contains.js b/Sprint-2/implement/contains.js
index bb215941d..36eacc776 100644
--- a/Sprint-2/implement/contains.js
+++ b/Sprint-2/implement/contains.js
@@ -1,14 +1,15 @@
-function contains(obj,propertyName) {
-  
-    
-if(Object.keys(obj).length===0){
-    return false
+function contains(obj, propertyName) {
+  if (typeof obj !== "object" || obj === null || Array.isArray(obj)) {
+    throw new Error("Invalid object");
+  }
+  if (Object.keys(obj).length === 0) {
+    return false;
+  }
+  if (Object.keys(obj).includes(propertyName)) {
+    return true;
+  }
+  return false;
 }
-if (Object.keys(obj).includes(propertyName)) {
-  return true;
-}
-return false
-}
-console.log(contains({a:"t",k:5},"o"));
+//console.log(contains({w:0}, [w]));
 
 module.exports = contains;
diff --git a/Sprint-2/implement/contains.test.js b/Sprint-2/implement/contains.test.js
index 59943cc1a..ce132b050 100644
--- a/Sprint-2/implement/contains.test.js
+++ b/Sprint-2/implement/contains.test.js
@@ -45,3 +45,7 @@ test("when contains is called with an object and a non-existing property name as
 // Given invalid parameters like an array
 // When passed to contains
 // Then it should return false or throw an error
+test("when contains is called with the string 'parameter' and propertyName='a' as arguments it throws an error", () => {
+  expect(() => contains("parameter", "a")).toThrow("Invalid object");
+});
+

From bbb05bc56bba4634a7bf9ac6835f4d2a58fd72ae Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Thu, 26 Feb 2026 15:00:36 +0000
Subject: [PATCH 09/32] remove commented-out console.log statement from
 contains function

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

diff --git a/Sprint-2/implement/contains.js b/Sprint-2/implement/contains.js
index 36eacc776..f5ee45f31 100644
--- a/Sprint-2/implement/contains.js
+++ b/Sprint-2/implement/contains.js
@@ -10,6 +10,6 @@ function contains(obj, propertyName) {
   }
   return false;
 }
-//console.log(contains({w:0}, [w]));
+
 
 module.exports = contains;

From 8f746c10c600da68cea0ac8cbaa46fcbe83878b0 Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Thu, 26 Feb 2026 15:17:48 +0000
Subject: [PATCH 10/32] implement test for createLookup function to validate
 country-currency code mapping

---
 Sprint-2/implement/lookup.test.js | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/Sprint-2/implement/lookup.test.js b/Sprint-2/implement/lookup.test.js
index 547e06c5a..9c37d1d6c 100644
--- a/Sprint-2/implement/lookup.test.js
+++ b/Sprint-2/implement/lookup.test.js
@@ -1,6 +1,16 @@
 const createLookup = require("./lookup.js");
 
-test.todo("creates a country currency code lookup for multiple codes");
+test("creates a country currency code lookup for multiple codes,when createLookup is passed[['US', 'USD'], ['CA', 'CAD']] it returns {'US': 'USD','CA': 'CAD'}", () => {
+  expect(
+    createLookup([
+      ["US", "USD"],
+      ["CA", "CAD"],
+    ])
+  ).toEqual({
+    US: "USD",
+    CA: "CAD",
+  });
+});
 
 /*
 

From 202e093b8d0eed2cd077e36397451002c22f496a Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Thu, 26 Feb 2026 15:29:43 +0000
Subject: [PATCH 11/32] implement createLookup function to map country codes to
 currency codes

---
 Sprint-2/implement/lookup.js | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/Sprint-2/implement/lookup.js b/Sprint-2/implement/lookup.js
index a6746e07f..ad2e95bda 100644
--- a/Sprint-2/implement/lookup.js
+++ b/Sprint-2/implement/lookup.js
@@ -1,5 +1,19 @@
-function createLookup() {
-  // implementation here
+function createLookup(array) {
+  let object={}
+  for(let element of array){
+    let key=element[0]
+    let value=element[1]
+    object[key]=value
+  }
+  return object
 }
 
+console.log(
+  createLookup([
+    ["US", "USD"],
+    ["CA", "CAD"],
+  ])
+);
+
+
 module.exports = createLookup;

From 1a3329e3fc6d53196795c1f4b38ec74acc327740 Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Thu, 26 Feb 2026 16:16:53 +0000
Subject: [PATCH 12/32] refactor parseQueryString function to improve key-value
 extraction logic

---
 Sprint-2/implement/querystring.js | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/Sprint-2/implement/querystring.js b/Sprint-2/implement/querystring.js
index 45ec4e5f3..e2c9f0d5d 100644
--- a/Sprint-2/implement/querystring.js
+++ b/Sprint-2/implement/querystring.js
@@ -6,11 +6,16 @@ function parseQueryString(queryString) {
   const keyValuePairs = queryString.split("&");
 
   for (const pair of keyValuePairs) {
-    const [key, value] = pair.split("=");
-    queryParams[key] = value;
+    const indexOfEqual = pair.indexOf("=");
+    const key = [pair.slice(0,indexOfEqual)];
+    const value = pair.slice(indexOfEqual+1);
+    queryParams[key]=value
+   
   }
 
   return queryParams;
 }
+console.log(parseQueryString("equation=x=y+1"));
+
 
 module.exports = parseQueryString;

From 3796ceab6e421038c2809ece2bdc8c51e18c483c Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Thu, 26 Feb 2026 16:41:55 +0000
Subject: [PATCH 13/32] fix: handle edge cases in parseQueryString function and
 update tests

---
 Sprint-2/implement/querystring.js      |  9 +++++++--
 Sprint-2/implement/querystring.test.js | 12 +++++++++++-
 2 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/Sprint-2/implement/querystring.js b/Sprint-2/implement/querystring.js
index e2c9f0d5d..7c38b1802 100644
--- a/Sprint-2/implement/querystring.js
+++ b/Sprint-2/implement/querystring.js
@@ -4,18 +4,23 @@ function parseQueryString(queryString) {
     return queryParams;
   }
   const keyValuePairs = queryString.split("&");
+  console.log(keyValuePairs);
+  
 
   for (const pair of keyValuePairs) {
     const indexOfEqual = pair.indexOf("=");
+    if(indexOfEqual===-1){
+      queryParams[pair]=""
+    }else{
     const key = [pair.slice(0,indexOfEqual)];
     const value = pair.slice(indexOfEqual+1);
     queryParams[key]=value
-   
+    }
   }
 
   return queryParams;
 }
-console.log(parseQueryString("equation=x=y+1"));
+console.log(parseQueryString("equation"));
 
 
 module.exports = parseQueryString;
diff --git a/Sprint-2/implement/querystring.test.js b/Sprint-2/implement/querystring.test.js
index 3e218b789..afa44712d 100644
--- a/Sprint-2/implement/querystring.test.js
+++ b/Sprint-2/implement/querystring.test.js
@@ -9,4 +9,14 @@ test("parses querystring values containing =", () => {
   expect(parseQueryString("equation=x=y+1")).toEqual({
     "equation": "x=y+1",
   });
-});
+}); 
+
+test("parses multiple querystring divided by &", () => {
+  expect(parseQueryString("equation=x=y+1&color=blue")).toEqual({
+    equation: "x=y+1",color:"blue"
+  });
+}); 
+
+test("it returns the value as an empty string if the querystring has no =",()=>{
+  expect(parseQueryString("day")).toEqual({day:""})
+})
\ No newline at end of file

From 0c37eb3881bd2a4e134479c8e1b3c0eff154c385 Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Thu, 26 Feb 2026 17:01:38 +0000
Subject: [PATCH 14/32] test: add case for empty key in querystring parsing

---
 Sprint-2/implement/querystring.test.js | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/Sprint-2/implement/querystring.test.js b/Sprint-2/implement/querystring.test.js
index afa44712d..6215cc3c0 100644
--- a/Sprint-2/implement/querystring.test.js
+++ b/Sprint-2/implement/querystring.test.js
@@ -19,4 +19,8 @@ test("parses multiple querystring divided by &", () => {
 
 test("it returns the value as an empty string if the querystring has no =",()=>{
   expect(parseQueryString("day")).toEqual({day:""})
-})
\ No newline at end of file
+})
+
+test("it returns the key as an empty string if the querystring has no nothing before =", () => {
+  expect(parseQueryString("=day")).toEqual({"":"day" });
+});
\ No newline at end of file

From 613c044246e8c17e3fa62708cbf01f7135db1e7b Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Thu, 26 Feb 2026 17:06:48 +0000
Subject: [PATCH 15/32] fix: clean up querystring parsing logic and improve
 test formatting

---
 Sprint-2/implement/querystring.js      | 17 +++++++----------
 Sprint-2/implement/querystring.test.js | 21 +++++++++++----------
 2 files changed, 18 insertions(+), 20 deletions(-)

diff --git a/Sprint-2/implement/querystring.js b/Sprint-2/implement/querystring.js
index 7c38b1802..8eec34cc0 100644
--- a/Sprint-2/implement/querystring.js
+++ b/Sprint-2/implement/querystring.js
@@ -4,23 +4,20 @@ function parseQueryString(queryString) {
     return queryParams;
   }
   const keyValuePairs = queryString.split("&");
-  console.log(keyValuePairs);
-  
 
   for (const pair of keyValuePairs) {
     const indexOfEqual = pair.indexOf("=");
-    if(indexOfEqual===-1){
-      queryParams[pair]=""
-    }else{
-    const key = [pair.slice(0,indexOfEqual)];
-    const value = pair.slice(indexOfEqual+1);
-    queryParams[key]=value
+    if (indexOfEqual === -1) {
+      queryParams[pair] = "";
+    } else {
+      const key = [pair.slice(0, indexOfEqual)];
+      const value = pair.slice(indexOfEqual + 1);
+      queryParams[key] = value;
     }
   }
 
   return queryParams;
 }
-console.log(parseQueryString("equation"));
-
+console.log(parseQueryString("=equationtu"));
 
 module.exports = parseQueryString;
diff --git a/Sprint-2/implement/querystring.test.js b/Sprint-2/implement/querystring.test.js
index 6215cc3c0..c127aecce 100644
--- a/Sprint-2/implement/querystring.test.js
+++ b/Sprint-2/implement/querystring.test.js
@@ -3,24 +3,25 @@
 // Below is one test case for an edge case the implementation doesn't handle well.
 // Fix the implementation for this test, and try to think of as many other edge cases as possible - write tests and fix those too.
 
-const parseQueryString = require("./querystring.js")
+const parseQueryString = require("./querystring.js");
 
 test("parses querystring values containing =", () => {
   expect(parseQueryString("equation=x=y+1")).toEqual({
-    "equation": "x=y+1",
+    equation: "x=y+1",
   });
-}); 
+});
 
 test("parses multiple querystring divided by &", () => {
   expect(parseQueryString("equation=x=y+1&color=blue")).toEqual({
-    equation: "x=y+1",color:"blue"
+    equation: "x=y+1",
+    color: "blue",
   });
-}); 
+});
 
-test("it returns the value as an empty string if the querystring has no =",()=>{
-  expect(parseQueryString("day")).toEqual({day:""})
-})
+test("it returns the value as an empty string if the querystring has no =", () => {
+  expect(parseQueryString("day")).toEqual({ day: "" });
+});
 
 test("it returns the key as an empty string if the querystring has no nothing before =", () => {
-  expect(parseQueryString("=day")).toEqual({"":"day" });
-});
\ No newline at end of file
+  expect(parseQueryString("=day")).toEqual({ "": "day" });
+});

From c279e017deb0b86ca3e282c67709798afa9b1c71 Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Fri, 27 Feb 2026 15:19:14 +0000
Subject: [PATCH 16/32] test: add tests for empty array and invalid input in
 tally function

---
 Sprint-2/implement/tally.test.js | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/Sprint-2/implement/tally.test.js b/Sprint-2/implement/tally.test.js
index 2ceffa8dd..e84084a17 100644
--- a/Sprint-2/implement/tally.test.js
+++ b/Sprint-2/implement/tally.test.js
@@ -1,7 +1,7 @@
 const tally = require("./tally.js");
 
 /**
- * tally array
+ * tally array 
  *
  * In this task, you'll need to implement a function called tally
  * that will take a list of items and count the frequency of each item
@@ -23,12 +23,22 @@ const tally = require("./tally.js");
 // Given an empty array
 // When passed to tally
 // Then it should return an empty object
-test.todo("tally on an empty array returns an empty object");
+test("when an empty array is passed to tally it returns an empty object",()=>{
+    expect(tally([])).toEqual({})
+});
 
 // Given an array with duplicate items
 // When passed to tally
 // Then it should return counts for each unique item
+test(
+  "when an array with duplicate items is passed to tally , it returns counts for each unique item",()=>{
+    expect(tally(["t","d",5,"t",5]))
+  }
+);
 
 // Given an invalid input like a string
 // When passed to tally
 // Then it should throw an error
+test("when a string is passed to tally it throws error",()=>{
+    expect(()=>tally("asd")).toThrow("Invalid input")
+})
\ No newline at end of file

From b93588f6fa47c6dbb105db017381f7d5a820ddaf Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Fri, 27 Feb 2026 15:19:28 +0000
Subject: [PATCH 17/32] feat: implement tally function to count occurrences in
 an array

---
 Sprint-2/implement/tally.js | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/Sprint-2/implement/tally.js b/Sprint-2/implement/tally.js
index f47321812..b228d7243 100644
--- a/Sprint-2/implement/tally.js
+++ b/Sprint-2/implement/tally.js
@@ -1,3 +1,13 @@
-function tally() {}
+function tally(array) {
+    
+  let obj = {};
+  array.forEach((elem) => {
+    obj[elem] = (obj[elem] || 0) + 1;
+  });
+  return obj;
+}
+console.log(tally("asd"));
+
+
 
 module.exports = tally;

From 8acd98bb420cdf2e4bf669c4c82cfadb1e12dad9 Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Fri, 27 Feb 2026 15:29:05 +0000
Subject: [PATCH 18/32] test: fix assertion in tally function tests and ensure
 proper formatting

---
 Sprint-2/implement/tally.test.js | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/Sprint-2/implement/tally.test.js b/Sprint-2/implement/tally.test.js
index e84084a17..e7e4c2685 100644
--- a/Sprint-2/implement/tally.test.js
+++ b/Sprint-2/implement/tally.test.js
@@ -32,13 +32,13 @@ test("when an empty array is passed to tally it returns an empty object",()=>{
 // Then it should return counts for each unique item
 test(
   "when an array with duplicate items is passed to tally , it returns counts for each unique item",()=>{
-    expect(tally(["t","d",5,"t",5]))
+    expect(tally(["t", "d", 5, "t", 5])).toEqual({ t: 2, d: 1, 5: 2 });
   }
 );
 
 // Given an invalid input like a string
 // When passed to tally
 // Then it should throw an error
-test("when a string is passed to tally it throws error",()=>{
-    expect(()=>tally("asd")).toThrow("Invalid input")
-})
\ No newline at end of file
+test("when a string is passed to tally it throws error", () => {
+  expect(() => tally("asd")).toThrow("Invalid input");
+});
\ No newline at end of file

From 327ba710d523b378065a107906f68ddd5d6d2a44 Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Fri, 27 Feb 2026 15:29:17 +0000
Subject: [PATCH 19/32] fix: add input validation to tally function to ensure
 array input

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

diff --git a/Sprint-2/implement/tally.js b/Sprint-2/implement/tally.js
index b228d7243..4dbdb47b0 100644
--- a/Sprint-2/implement/tally.js
+++ b/Sprint-2/implement/tally.js
@@ -1,12 +1,14 @@
 function tally(array) {
-    
+   if(!Array.isArray(array)){
+    throw new Error("Invalid input");
+   } 
   let obj = {};
   array.forEach((elem) => {
     obj[elem] = (obj[elem] || 0) + 1;
   });
   return obj;
 }
-console.log(tally("asd"));
+//console.log(tally("asd"));
 
 
 

From 48a17dc50d87821dfa595aba6d4ddaf9cc5725bf Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Fri, 27 Feb 2026 15:29:55 +0000
Subject: [PATCH 20/32] fix: improve formatting and consistency in tally
 function and tests

---
 Sprint-2/implement/tally.js      |  7 ++-----
 Sprint-2/implement/tally.test.js | 16 +++++++---------
 2 files changed, 9 insertions(+), 14 deletions(-)

diff --git a/Sprint-2/implement/tally.js b/Sprint-2/implement/tally.js
index 4dbdb47b0..d169c1f7e 100644
--- a/Sprint-2/implement/tally.js
+++ b/Sprint-2/implement/tally.js
@@ -1,15 +1,12 @@
 function tally(array) {
-   if(!Array.isArray(array)){
+  if (!Array.isArray(array)) {
     throw new Error("Invalid input");
-   } 
+  }
   let obj = {};
   array.forEach((elem) => {
     obj[elem] = (obj[elem] || 0) + 1;
   });
   return obj;
 }
-//console.log(tally("asd"));
-
-
 
 module.exports = tally;
diff --git a/Sprint-2/implement/tally.test.js b/Sprint-2/implement/tally.test.js
index e7e4c2685..c4a934900 100644
--- a/Sprint-2/implement/tally.test.js
+++ b/Sprint-2/implement/tally.test.js
@@ -1,7 +1,7 @@
 const tally = require("./tally.js");
 
 /**
- * tally array 
+ * tally array
  *
  * In this task, you'll need to implement a function called tally
  * that will take a list of items and count the frequency of each item
@@ -23,22 +23,20 @@ const tally = require("./tally.js");
 // Given an empty array
 // When passed to tally
 // Then it should return an empty object
-test("when an empty array is passed to tally it returns an empty object",()=>{
-    expect(tally([])).toEqual({})
+test("when an empty array is passed to tally it returns an empty object", () => {
+  expect(tally([])).toEqual({});
 });
 
 // Given an array with duplicate items
 // When passed to tally
 // Then it should return counts for each unique item
-test(
-  "when an array with duplicate items is passed to tally , it returns counts for each unique item",()=>{
-    expect(tally(["t", "d", 5, "t", 5])).toEqual({ t: 2, d: 1, 5: 2 });
-  }
-);
+test("when an array with duplicate items is passed to tally , it returns counts for each unique item", () => {
+  expect(tally(["t", "d", 5, "t", 5])).toEqual({ t: 2, d: 1, 5: 2 });
+});
 
 // Given an invalid input like a string
 // When passed to tally
 // Then it should throw an error
 test("when a string is passed to tally it throws error", () => {
   expect(() => tally("asd")).toThrow("Invalid input");
-});
\ No newline at end of file
+});

From 46c15fa148e6e33d671edeadaba5a36e864e0c5d Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Fri, 27 Feb 2026 15:42:54 +0000
Subject: [PATCH 21/32] fix: correct implementation of invert function to
 properly swap keys and values, add comments to explain the process

---
 Sprint-2/interpret/invert.js | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/Sprint-2/interpret/invert.js b/Sprint-2/interpret/invert.js
index bb353fb1f..5a1d14277 100644
--- a/Sprint-2/interpret/invert.js
+++ b/Sprint-2/interpret/invert.js
@@ -10,20 +10,26 @@ function invert(obj) {
   const invertedObj = {};
 
   for (const [key, value] of Object.entries(obj)) {
-    invertedObj.key = value;
+    invertedObj[value] = key;
   }
 
   return invertedObj;
 }
+console.log(invert({a:1,b:2}));
 
 // 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: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?
+//it returns the key:value pairs of obj,it's needed to extract those pairs from obj
 
 // d) Explain why the current return value is different from the target output
+//because it's using invertedObj.key = value; instead of invertedObj[value] = key;
 
 // e) Fix the implementation of invert (and write tests to prove it's fixed!)

From b6692593be475e8e132561eeb2fd5aeedb7a037f Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Fri, 27 Feb 2026 15:43:22 +0000
Subject: [PATCH 22/32] test: add initial test suite for invert function

---
 Sprint-2/interpret/invert.test.js | 0
 1 file changed, 0 insertions(+), 0 deletions(-)
 create mode 100644 Sprint-2/interpret/invert.test.js

diff --git a/Sprint-2/interpret/invert.test.js b/Sprint-2/interpret/invert.test.js
new file mode 100644
index 000000000..e69de29bb

From 4c94700ca8d6b2ea381e571bb70d8045a35c2c21 Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Fri, 27 Feb 2026 15:51:32 +0000
Subject: [PATCH 23/32] fix: add input validation to invert function to handle
 non-object inputs and improve error handling

---
 Sprint-2/interpret/invert.js      | 4 +++-
 Sprint-2/interpret/invert.test.js | 4 ++++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/Sprint-2/interpret/invert.js b/Sprint-2/interpret/invert.js
index 5a1d14277..2d3e410ae 100644
--- a/Sprint-2/interpret/invert.js
+++ b/Sprint-2/interpret/invert.js
@@ -7,6 +7,7 @@
 // E.g. invert({x : 10, y : 20}), target output: {"10": "x", "20": "y"}
 
 function invert(obj) {
+  if(typeof obj!=="object" || Array.isArray(obj)|| obj===null)throw new Error("Invalid input");
   const invertedObj = {};
 
   for (const [key, value] of Object.entries(obj)) {
@@ -15,7 +16,8 @@ function invert(obj) {
 
   return invertedObj;
 }
-console.log(invert({a:1,b:2}));
+console.log(invert(null));
+module.exports=invert
 
 // a) What is the current return value when invert is called with { a : 1 }
 //{key=1}
diff --git a/Sprint-2/interpret/invert.test.js b/Sprint-2/interpret/invert.test.js
index e69de29bb..858c6ce86 100644
--- a/Sprint-2/interpret/invert.test.js
+++ b/Sprint-2/interpret/invert.test.js
@@ -0,0 +1,4 @@
+const invert=require("./invert.js")
+test("when passed a string invert will throw error",()=>{
+    expect(()=>invert("asd")).toThrow("Invalid input")
+})
\ No newline at end of file

From b80bd10cef22d64bf3377c01b9d6afa01740531d Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Fri, 27 Feb 2026 16:02:45 +0000
Subject: [PATCH 24/32] fix: update invert function test to handle null input
 and ensure proper error handling

---
 Sprint-2/interpret/invert.js      | 2 +-
 Sprint-2/interpret/invert.test.js | 3 ++-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/Sprint-2/interpret/invert.js b/Sprint-2/interpret/invert.js
index 2d3e410ae..b1e6331e0 100644
--- a/Sprint-2/interpret/invert.js
+++ b/Sprint-2/interpret/invert.js
@@ -16,7 +16,7 @@ function invert(obj) {
 
   return invertedObj;
 }
-console.log(invert(null));
+console.log(invert({}));
 module.exports=invert
 
 // a) What is the current return value when invert is called with { a : 1 }
diff --git a/Sprint-2/interpret/invert.test.js b/Sprint-2/interpret/invert.test.js
index 858c6ce86..327413ab4 100644
--- a/Sprint-2/interpret/invert.test.js
+++ b/Sprint-2/interpret/invert.test.js
@@ -1,4 +1,5 @@
 const invert=require("./invert.js")
 test("when passed a string invert will throw error",()=>{
     expect(()=>invert("asd")).toThrow("Invalid input")
-})
\ No newline at end of file
+})
+

From 5b1dab3e92f11e53226932d376c7102de184af65 Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Fri, 27 Feb 2026 16:15:32 +0000
Subject: [PATCH 25/32] test: add additional test cases for invert function to
 validate behavior with various inputs

---
 Sprint-2/interpret/invert.test.js | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/Sprint-2/interpret/invert.test.js b/Sprint-2/interpret/invert.test.js
index 327413ab4..6c79bb29f 100644
--- a/Sprint-2/interpret/invert.test.js
+++ b/Sprint-2/interpret/invert.test.js
@@ -3,3 +3,14 @@ test("when passed a string invert will throw error",()=>{
     expect(()=>invert("asd")).toThrow("Invalid input")
 })
 
+test("when passed an empty object, invert returns an empty object",()=>{
+    expect(invert({})).toEqual({})
+})
+
+test("when passed an  object containing one key:value pair, invert returns an  object containing value:key", () => {
+  expect(invert({a:1})).toEqual({"1":"a"});
+});
+
+test("when passed an  object containing multiple key:value pairs, invert returns an  object containing value:key pairs", () => {
+  expect(invert({ a: 1,apple:"red",month:"September" })).toEqual({ 1: "a","red":"apple","September":"month" });
+});
\ No newline at end of file

From 9935333615332309297d1e919841fa002bdbb09f Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Fri, 27 Feb 2026 16:15:56 +0000
Subject: [PATCH 26/32] fix: improve input validation in invert function and
 update test cases for consistency

---
 Sprint-2/interpret/invert.js      |  7 ++++---
 Sprint-2/interpret/invert.test.js | 24 ++++++++++++++----------
 2 files changed, 18 insertions(+), 13 deletions(-)

diff --git a/Sprint-2/interpret/invert.js b/Sprint-2/interpret/invert.js
index b1e6331e0..25de7b376 100644
--- a/Sprint-2/interpret/invert.js
+++ b/Sprint-2/interpret/invert.js
@@ -7,7 +7,8 @@
 // E.g. invert({x : 10, y : 20}), target output: {"10": "x", "20": "y"}
 
 function invert(obj) {
-  if(typeof obj!=="object" || Array.isArray(obj)|| obj===null)throw new Error("Invalid input");
+  if (typeof obj !== "object" || Array.isArray(obj) || obj === null)
+    throw new Error("Invalid input");
   const invertedObj = {};
 
   for (const [key, value] of Object.entries(obj)) {
@@ -16,8 +17,8 @@ function invert(obj) {
 
   return invertedObj;
 }
-console.log(invert({}));
-module.exports=invert
+
+module.exports = invert;
 
 // a) What is the current return value when invert is called with { a : 1 }
 //{key=1}
diff --git a/Sprint-2/interpret/invert.test.js b/Sprint-2/interpret/invert.test.js
index 6c79bb29f..56c6aef71 100644
--- a/Sprint-2/interpret/invert.test.js
+++ b/Sprint-2/interpret/invert.test.js
@@ -1,16 +1,20 @@
-const invert=require("./invert.js")
-test("when passed a string invert will throw error",()=>{
-    expect(()=>invert("asd")).toThrow("Invalid input")
-})
+const invert = require("./invert.js");
+test("when passed a string invert will throw error", () => {
+  expect(() => invert("asd")).toThrow("Invalid input");
+});
 
-test("when passed an empty object, invert returns an empty object",()=>{
-    expect(invert({})).toEqual({})
-})
+test("when passed an empty object, invert returns an empty object", () => {
+  expect(invert({})).toEqual({});
+});
 
 test("when passed an  object containing one key:value pair, invert returns an  object containing value:key", () => {
-  expect(invert({a:1})).toEqual({"1":"a"});
+  expect(invert({ a: 1 })).toEqual({ 1: "a" });
 });
 
 test("when passed an  object containing multiple key:value pairs, invert returns an  object containing value:key pairs", () => {
-  expect(invert({ a: 1,apple:"red",month:"September" })).toEqual({ 1: "a","red":"apple","September":"month" });
-});
\ No newline at end of file
+  expect(invert({ a: 1, apple: "red", month: "September" })).toEqual({
+    1: "a",
+    red: "apple",
+    September: "month",
+  });
+});

From 12de278a96ac0a9720aef66aa01198e8d9fe15ec Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Fri, 27 Feb 2026 17:19:47 +0000
Subject: [PATCH 27/32] refactor: split calculateMode into smaller functions
 for improved readability

---
 Sprint-2/stretch/mode.js      | 14 +++++++++++---
 Sprint-2/stretch/mode.test.js |  2 +-
 2 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/Sprint-2/stretch/mode.js b/Sprint-2/stretch/mode.js
index 3f7609d79..d7f149f48 100644
--- a/Sprint-2/stretch/mode.js
+++ b/Sprint-2/stretch/mode.js
@@ -9,7 +9,12 @@
 // into smaller functions using the stages above
 
 function calculateMode(list) {
-  // track frequency of each value
+  let freqs = elementFrequency(list);
+
+  return maxFrequency(freqs);
+}
+
+function elementFrequency(list) {
   let freqs = new Map();
 
   for (let num of list) {
@@ -19,8 +24,10 @@ function calculateMode(list) {
 
     freqs.set(num, (freqs.get(num) || 0) + 1);
   }
+  return freqs;
+}
 
-  // Find the value with the highest frequency
+function maxFrequency(freqs) {
   let maxFreq = 0;
   let mode;
   for (let [num, freq] of freqs) {
@@ -29,8 +36,9 @@ function calculateMode(list) {
       maxFreq = freq;
     }
   }
-
   return maxFreq === 0 ? NaN : mode;
 }
 
+
+
 module.exports = calculateMode;
diff --git a/Sprint-2/stretch/mode.test.js b/Sprint-2/stretch/mode.test.js
index ca33c28a3..1f2d72353 100644
--- a/Sprint-2/stretch/mode.test.js
+++ b/Sprint-2/stretch/mode.test.js
@@ -9,7 +9,7 @@ const calculateMode = require("./mode.js");
 // Example:
 // Given [2,4,1,2,3,2,1]
 // When calculateMode is called on [2,4,1,2,3,2,1]
-// Then it should return 2 */
+// Then it should return 2 */ 
 
 describe("calculateMode()", () => {
   test("returns the most frequent number in an array", () => {

From fad45bea9a8ce4a3690cb802aa5c1ffa29bf2785 Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Fri, 27 Feb 2026 22:00:55 +0000
Subject: [PATCH 28/32] fix: implement countWords function to count word
 occurrences in a string

---
 Sprint-2/stretch/count-words.js | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/Sprint-2/stretch/count-words.js b/Sprint-2/stretch/count-words.js
index 8e85d19d7..7ce05352b 100644
--- a/Sprint-2/stretch/count-words.js
+++ b/Sprint-2/stretch/count-words.js
@@ -26,3 +26,15 @@
 
 3. Order the results to find out which word is the most common in the input
 */
+function countWords(string) {
+  const noPunctuation = string.replace(/[.,!?]/g,"");
+  const array = noPunctuation.split(" ");
+  
+  
+  let object = {};
+  array.forEach((word) => {
+    object[word] = (object[word] || 0) + 1;
+  });
+  return array
+}
+console.log(countWords("you, and .me? and you me me"));

From fe23a35290787b22a3eb49228728849221a19b00 Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Fri, 27 Feb 2026 22:03:24 +0000
Subject: [PATCH 29/32] fix: ensure case-insensitive word counting and return
 correct object in countWords function

---
 Sprint-2/stretch/count-words.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/Sprint-2/stretch/count-words.js b/Sprint-2/stretch/count-words.js
index 7ce05352b..1faaa32a2 100644
--- a/Sprint-2/stretch/count-words.js
+++ b/Sprint-2/stretch/count-words.js
@@ -28,13 +28,13 @@
 */
 function countWords(string) {
   const noPunctuation = string.replace(/[.,!?]/g,"");
-  const array = noPunctuation.split(" ");
+  const array = noPunctuation.toLowerCase().split(" ");
   
   
   let object = {};
   array.forEach((word) => {
     object[word] = (object[word] || 0) + 1;
   });
-  return array
+  return object
 }
-console.log(countWords("you, and .me? and you me me"));
+console.log(countWords("You, and .me? and you me me"));

From 6fc416e92d0d6cbdb14af766c78a74a509bc150d Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Fri, 27 Feb 2026 22:15:17 +0000
Subject: [PATCH 30/32] fix: update countWords function to return sorted word
 counts

---
 Sprint-2/stretch/count-words.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Sprint-2/stretch/count-words.js b/Sprint-2/stretch/count-words.js
index 1faaa32a2..6ab05ee67 100644
--- a/Sprint-2/stretch/count-words.js
+++ b/Sprint-2/stretch/count-words.js
@@ -35,6 +35,6 @@ function countWords(string) {
   array.forEach((word) => {
     object[word] = (object[word] || 0) + 1;
   });
-  return object
+  return Object.values(object).sort((a,b)=>b-a)/////?????? stuck on how to order it
 }
 console.log(countWords("You, and .me? and you me me"));

From 6e3ea519f44a4831d0472ef9b1a601005ced7d60 Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Sun, 1 Mar 2026 12:03:46 +0000
Subject: [PATCH 31/32] fix: correct total calculation in totalTill function by
 parsing coin values

---
 Sprint-2/stretch/till.js | 23 ++++++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/Sprint-2/stretch/till.js b/Sprint-2/stretch/till.js
index 6a08532e7..7f926ad82 100644
--- a/Sprint-2/stretch/till.js
+++ b/Sprint-2/stretch/till.js
@@ -8,7 +8,10 @@ function totalTill(till) {
   let total = 0;
 
   for (const [coin, quantity] of Object.entries(till)) {
-    total += coin * quantity;
+    const coinWithOutTrailingP = coin.slice(0, -1);
+    const numberCoin = +coinWithOutTrailingP;
+
+    total += numberCoin * quantity;
   }
 
   return `£${total / 100}`;
@@ -21,11 +24,29 @@ const till = {
   "20p": 10,
 };
 const totalAmount = totalTill(till);
+console.log(totalAmount);
 
 // a) What is the target output when totalTill is called with the till object
+//£4.40
 
 // b) Why do we need to use Object.entries inside the for...of loop in this function?
+// to get the key value pairs
 
 // c) What does coin * quantity evaluate to inside the for...of loop?
+//NaN
 
 // d) Write a test for this function to check it works and then fix the implementation of totalTill
+// const till1 = {
+//   "1p": 10,
+//   "5p": 6,
+//   "50p": 4,
+//   "20p": 10,
+// };
+
+const currentOutput = totalTill(till);
+const expectedOutput = "£4.4";
+
+console.assert(
+  currentOutput === expectedOutput,
+  `Expected ${expectedOutput}, got ${currentOutput}`
+);

From 24a4c748c44fb7f0ab1509531348e5ea2ef1cf0e Mon Sep 17 00:00:00 2001
From: alexandru-pocovnicu
 <109530683+alexandru-pocovnicu@users.noreply.github.com>
Date: Thu, 12 Mar 2026 10:58:45 +0000
Subject: [PATCH 32/32] fix: update contains function to throw error for empty
 objects instead of returning false

---
 Sprint-2/implement/contains.js      | 11 +++++++----
 Sprint-2/implement/contains.test.js |  2 +-
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/Sprint-2/implement/contains.js b/Sprint-2/implement/contains.js
index f5ee45f31..58f57414e 100644
--- a/Sprint-2/implement/contains.js
+++ b/Sprint-2/implement/contains.js
@@ -1,10 +1,13 @@
 function contains(obj, propertyName) {
-  if (typeof obj !== "object" || obj === null || Array.isArray(obj)) {
+  if (
+    typeof obj !== "object" ||
+    obj === null ||
+    Array.isArray(obj) ||
+    Object.keys(obj).length === 0
+  ) {
     throw new Error("Invalid object");
   }
-  if (Object.keys(obj).length === 0) {
-    return false;
-  }
+  
   if (Object.keys(obj).includes(propertyName)) {
     return true;
   }
diff --git a/Sprint-2/implement/contains.test.js b/Sprint-2/implement/contains.test.js
index ce132b050..699a3fccf 100644
--- a/Sprint-2/implement/contains.test.js
+++ b/Sprint-2/implement/contains.test.js
@@ -21,7 +21,7 @@ as the object doesn't contains a key of 'c'
 // When passed to contains
 // Then it should return false
 test("contains on empty object and propertyName='k' returns false", () => {
-  expect(contains({}, "k")).toEqual(false);
+  expect(()=>contains({}, "k")).toThrow("Invalid object");
 });
 
 // Given an object with properties