London | ITP-May-2025 | Seddiq Azam | Module-Structuring-and-Testing-Data | Sprint-1

Sprint-1/1-key-exercises/1-count.js

@@ -3,4 +3,13 @@ let count = 0;
 count = count + 1;
 
 // Line 1 is a variable declaration, creating the count variable with an initial value of 0
-// Describe what line 3 is doing, in particular focus on what = is doing
+// Describe what line 3 is doing, in particular, focus on what = is doing
+
+
+//The answers:
+//  In line 1, the variable `count` is declared and initialised with the value `0`.  
+//  In line 3, the value of `count` is updated by assigning it the result of `count + 1`. Since the initial value was `0`, the new value becomes `0 + 1`, which is `1`.  
+
+//  In programming terms, this means the variable `count` is incremented by `1`.  
+
+//  The equals sign (`=`) is the assignment operator. It assigns the value on the right side of the `=` to the variable on the left side.

Sprint-1/1-key-exercises/2-initials.js

@@ -5,7 +5,8 @@ let lastName = "Johnson";
 // Declare a variable called initials that stores the first character of each string.
 // This should produce the string "CKJ", but you must not write the characters C, K, or J in the code of your solution.
 
-let initials = ``;
+let initials = firstName[0] + middleName[0] + lastName[0];
+console.log(initials);
 
 // https://www.google.com/search?q=get+first+character+of+string+mdn
 

Sprint-1/1-key-exercises/3-paths.js

@@ -17,7 +17,10 @@ console.log(`The base part of ${filePath} is ${base}`);
 // Create a variable to store the dir part of the filePath variable
 // Create a variable to store the ext part of the variable
 
-const dir = ;
-const ext = ;
+const dir = filePath.slice(0, lastSlashIndex);
+console.log(`The dir part of ${filePath} is: ${dir}`);
 
-// https://www.google.com/search?q=slice+mdn
+const ext = base.slice(base.lastIndexOf(".") + 1);
+console.log(`The ext part of ${filePath} is: ${ext}`);
+
+// https://www.google.com/search?q=slice+mdn

Sprint-1/1-key-exercises/4-random.js

@@ -7,3 +7,21 @@ const num = Math.floor(Math.random() * (maximum - minimum + 1)) + minimum;
 // Try breaking down the expression and using documentation to explain what it means
 // It will help to think about the order in which expressions are evaluated
 // Try logging the value of num and running the program several times to build an idea of what the program is doing
+
+
+// Answers:
+
+//  num is a variable that stores a random integer between 1 and 100, inclusive.
+//	•	Math.floor() rounds a number down to the nearest integer.
+//	•	Math.random() generates a decimal number between 0 (inclusive) and 1 (exclusive).
+//	•	(maximum - minimum + 1) calculates the size of the range of possible numbers. Here, it is 100 - 1 + 1 = 100.
+//	•	minimum is added at the end to shift the result so that it falls within the desired range starting from the minimum value.
+
+// How the formula works:
+//	1.	Calculate the size of the range using (maximum - minimum + 1). In this example, with maximum = 100 and minimum = 1, the range size is 100 - 1 + 1 = 100.
+//	2.	Math.random() generates a decimal number between 0 (inclusive) and 1 (exclusive), such as 0.0001 or 0.9999.
+//	3.	Multiply the result of Math.random() by the range size to scale the number. For example: 0.9999 * 100 = 99.99.
+//	4.	Use Math.floor() to round the scaled number down to the nearest whole number. For example: Math.floor(99.99) = 99.
+//	5.	Add the minimum value to shift the number into the correct range. For example: 99 + 1 = 100.
+
+//  This ensures that num will always be an integer between 1 and 100, inclusive.

Sprint-1/2-mandatory-errors/1.js

@@ -1,4 +1,6 @@
 // trying to create an age variable and then reassign the value by 1
 
-const age = 33;
+let age = 33;
 age = age + 1;
+
+console.log(age);

Sprint-1/2-mandatory-errors/2.js

@@ -1,5 +1,5 @@
 // Currently trying to print the string "I was born in Bolton" but it isn't working...
 // what's the error ?
 
-console.log(`I was born in ${cityOfBirth}`);
 const cityOfBirth = "Bolton";
+console.log(`I was born in ${cityOfBirth}`);

Sprint-1/2-mandatory-errors/3.js

@@ -7,3 +7,17 @@ const last4Digits = cardNumber.slice(-4);
 // Then run the code and see what error it gives.
 // Consider: Why does it give this error? Is this what I predicted? If not, what's different?
 // Then try updating the expression last4Digits is assigned to, in order to get the correct value
+
+
+
+// Answers:
+
+//  The code isn’t working because the variable cardNumber is a number, not a string or an array. 
+//  The slice method only works on strings or arrays. 
+//  Therefore, calling const last4Digits = cardNumber.slice(-4); causes an error because .slice is not a function available for numbers.
+
+//  I predicted this error because the variable cardNumber was not assigned as a string.
+
+const last4Digits = cardNumber.toString().slice(-4);
+
+console.log(last4Digits);

Sprint-1/2-mandatory-errors/4.js

@@ -1,2 +1,8 @@
-const 12HourClockTime = "20:53";
-const 24hourClockTime = "08:53";
+const hour24ClockTime = "20:53";
+console.log(hour24ClockTime);
+
+const hour12ClockTime = "08:53";
+console.log(hour12ClockTime);
+
+// The variables were renamed because JavaScript does not allow variables to start with numbers
+// camelCase format used for variable names

Sprint-1/3-mandatory-interpret/1-percentage-change.js

@@ -11,12 +11,49 @@ console.log(`The percentage change is ${percentageChange}`);
 
 // Read the code and then answer the questions below
 
+//-----------------------------------------------------------------------------------------------
+
 // a) How many function calls are there in this file? Write down all the lines where a function call is made
 
+//   There are 5 function calls:
+
+//	•	Line 4 — carPrice = Number(carPrice.replaceAll(",", ""));
+//	•	carPrice.replaceAll()
+//	•	Number()
+
+//	•	Line 5 — priceAfterOneYear = Number(priceAfterOneYear.replaceAll(",", ""));
+//	•	priceAfterOneYear.replaceAll()
+//	•	Number()
+
+//	•	Line 10 — console.log()
+
+//-----------------------------------------------------------------------------------------------
 // b) Run the code and identify the line where the error is coming from - why is this error occurring? How can you fix this problem?
 
+//    There is a syntax error on line 5. 
+//    The two strings inside the replaceAll method are missing a comma separator, causing them to be concatenated incorrectly. 
+//    Adding the missing comma between the two arguments will fix the problem.
+
+//-----------------------------------------------------------------------------------------------
+
 // c) Identify all the lines that are variable reassignment statements
 
+//    •	Line 4 — reassignment of carPrice
+//    •	Line 5 — reassignment of priceAfterOneYear
+
+//-----------------------------------------------------------------------------------------------
+
 // d) Identify all the lines that are variable declarations
 
+    // Line 1 - let   (let carPrice = "10,000";)
+    // Line 2 - let    (let priceAfterOneYear = "8,543";)
+    // Line 7 - const    (const priceDifference = carPrice - priceAfterOneYear;)
+    // Line 8 - const    (const percentageChange = (priceDifference / carPrice) * 100;)
+
+//-----------------------------------------------------------------------------------------------
 // e) Describe what the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression?
+
+//    The value of carPrice is initially a string that includes commas, for example "10,000". 
+//    JavaScript cannot perform numerical calculations on strings containing commas, as it does not recognise them as valid numbers.
+//    The method .replaceAll(",", "") removes all commas from the string, turning "10,000" into "10000".
+//    Finally, the Number() function converts the resulting string "10000" into the numeric value 10000, which allows mathematical operations to be performed on it.

Sprint-1/3-mandatory-interpret/2-time-format.js

@@ -11,15 +11,105 @@ console.log(result);
 
 // For the piece of code above, read the code and then answer the following questions
 
+//-----------------------------------------------------------------------------------------------
 // a) How many variable declarations are there in this program?
 
+    // There are six variable declarations in the code:
+
+    // Line 1 – const movieLength:
+    // Stores the total duration of the movie in seconds.
+
+    // Line 3 – const remainingSeconds:
+    // Calculates the number of seconds remaining after converting to full minutes.
+
+    // Line 4 – const totalMinutes:
+    // Stores the total number of full minutes, excluding the leftover seconds.
+
+    // Line 6 – const remainingMinutes:
+    // Calculates the remaining minutes after converting to full hours.
+
+    // Line 7 – const totalHours:
+    // Stores the total number of full hours in the movie duration.
+
+    // Line 9 – const result:
+    // Constructs the final time in "HH:MM:SS" format as a string.
+
+//-----------------------------------------------------------------------------------------------
 // b) How many function calls are there?
 
+    // There is one function call in the code:
+
+    // console.log(result):
+    // This function outputs the final formatted time (in "HH:MM:SS" format) to the console.
+
+//-----------------------------------------------------------------------------------------------
 // c) Using documentation, explain what the expression movieLength % 60 represents
 // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Arithmetic_Operators
 
+    // The expression "movieLength % 60" uses the modulo operator, 
+    // which is an arithmetic operation that returns the remainder 
+    // after division.
+
+    // In this context, it helps determine how many seconds are left 
+    // after converting the total movie length into full minutes.
+
+    // For example:
+    // movieLength = 8784 seconds
+    // 8784 ÷ 60 = 146 full minutes with a remainder of 24 seconds
+    // So, movieLength % 60 = 24
+
+    // These 24 seconds are what remain after dividing the movie length 
+    // into whole minutes.
+
+    // If we subtract the 24 seconds from the total:
+    // 8784 - 24 = 8760 seconds
+    // Then: 8760 ÷ 60 = 146 full minutes
+
+//-----------------------------------------------------------------------------------------------
 // d) Interpret line 4, what does the expression assigned to totalMinutes mean?
 
+    // (movieLength - remainingSeconds):
+    // This subtracts the "remainingSeconds" (24) from the total "movieLength" (8784 seconds). 
+    // The purpose is to remove the leftover seconds, leaving only the number of seconds 
+    // that make up complete minutes.
+
+    // / 60:
+    // This divides the result by 60 (since there are 60 seconds in a minute) 
+    // to convert the remaining seconds into full minutes.
+
+    // totalMinutes:
+    // This represents the total number of whole minutes in the movie, 
+    // which in this example is 146.
+
+//-----------------------------------------------------------------------------------------------
 // e) What do you think the variable result represents? Can you think of a better name for this variable?
 
+    // The variable `const result = `${totalHours}:${remainingMinutes}:${remainingSeconds}`;` 
+    // represents the length of the movie formatted as hours:minutes:seconds (HH:MM:SS).
+
+    // A more descriptive name for this variable could be "movieDurationTime", 
+    // as it clearly indicates that the value represents the movie's duration 
+    // in a time format.
+
+//-----------------------------------------------------------------------------------------------
 // f) Try experimenting with different values of movieLength. Will this code work for all values of movieLength? Explain your answer
+
+    // This code will not display properly for movies with a duration of 0 seconds, 
+    // as the output would appear as "0:0:0", which is not well-formatted.
+
+    // We can fix this by applying the .padStart() method to each time unit 
+    // (hours, minutes, and seconds) to ensure they are always displayed 
+    // with two digits — for example, "00:00:00".
+
+    // We use .padStart() on string values because all the time units 
+    // are integers, and this method works on strings.
+
+
+
+
+
+
+
+
+
+

Sprint-1/3-mandatory-interpret/3-to-pounds.js

@@ -25,3 +25,31 @@ console.log(`£${pounds}.${pence}`);
 
 // To begin, we can start with
 // 1. const penceString = "399p": initialises a string variable with the value "399p"
+
+// 2. const penceStringWithoutTrailingP = penceString.substring(0, penceString.length - 1);
+// This line removes the last character from the input string, which is the letter "p" (representing pence).
+// The reason we remove "p" is that we can't perform calculations on a string that includes non-numeric characters.
+
+
+// 3. const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0");
+// This line ensures the string is at least three characters long by padding it with leading zeros if necessary.
+// This formatting allows us to easily separate the value into pounds and pence — where the last two digits represent pence and the remaining digits represent pounds.
+
+
+// 4. const pounds = paddedPenceNumberString.substring(0, paddedPenceNumberString.length - 2);
+// This line extracts the pound portion of the value by taking all characters except the last two.
+// For example, if the input is "399p", it becomes "399", and this line extracts "3" as the pound value.
+
+
+// 5. const pence = paddedPenceNumberString
+//    .substring(paddedPenceNumberString.length - 2)
+//    .padEnd(2, "0");
+// This line extracts the last two digits, which represent the pence.
+// The `.padEnd(2, "0")` ensures that even if the pence value is only one digit (e.g., "5"), it becomes two digits (e.g., "05").
+// So "5p" would correctly display as "£0.05" instead of "£0.5".
+
+
+// 6. console.log(`£${pounds}.${pence}`);
+// This line prints the final result in the correct British currency format.
+// If the input is "399p", the output will be "£3.99".
+// This step is important for presenting the value in a user-friendly and readable format.

Sprint-1/4-stretch-explore/chrome.md

@@ -16,3 +16,33 @@ Now try invoking the function `prompt` with a string input of `"What is your nam
 
 What effect does calling the `prompt` function have?
 What is the return value of `prompt`?
+
+
+## What I Did in the Chrome Console
+
+1. I opened a new page in Google Chrome.  
+2. I right-clicked on the page and selected **Inspect**.  
+3. In the Developer Tools window, I clicked on the **Console** tab.  
+4. I typed the function `alert("Hello world!");` and pressed **Enter**.  
+5. A pop-up appeared displaying the message **"Hello world!"**. I clicked **OK** to close it.  
+6. Next, I typed `const myName = prompt("What is your name?");` and pressed **Enter**.  
+7. A dialog box appeared with the message **"What is your name?"** and a text input field.  
+8. I entered my name, **Sed**, into the input box and clicked **OK**.  
+9. The browser stored my input in the variable `myName`.  
+10. Then, I typed `console.log("You entered:", myName);` and pressed **Enter**.  
+11. The console displayed: `You entered: Sed`
+
+---
+
+## What Effect Does Calling the `prompt()` Function Have?
+
+It displays a dialog box that prompts the user to enter information.  
+If the result is assigned (e.g., `const myName = prompt("What is your name?");`),  
+the user's input is stored in the variable (in this case, `myName`).
+
+---
+
+## What Is the Return Value of `prompt()`?
+
+The value entered by the user is returned as a **string**.  
+If the user clicks **Cancel**, the return value is **`null`**.

Sprint-1/4-stretch-explore/objects.md

@@ -14,3 +14,42 @@ Answer the following questions:
 
 What does `console` store?
 What does the syntax `console.log` or `console.assert` mean? In particular, what does the `.` mean?
+
+Answers: 
+
+# Exploring the Chrome DevTools Console
+
+**Open the Chrome DevTools Console, type `console.log` and then hit Enter**  
+Done.
+
+**What output do you get?**  
+I got:  
+ƒ log() { [native code] }
+
+**Now enter just `console` in the Console, what output do you get back?**  
+I got:  
+console {debug: ƒ, error: ƒ, info: ƒ, log: ƒ, warn: ƒ, …}
+
+**Try also entering `typeof console`**  
+I got:  
+"object"
+
+---
+
+## What does `console` store?
+
+`console` is a JavaScript object that provides access to the browser's debugging console.  
+It stores functions such as `log`, `error`, `warn`, etc., which are used to track or print information while the code runs.
+
+---
+
+## What does the syntax `console.log` or `console.assert` mean? In particular, what does the `.` mean?
+
+It means to access the `log` function that belongs to the `console` object.
+
+---
+
+## What does the `.` mean?
+
+The dot (`.`) is a notation in JavaScript used to access a property or function on an object.  
+So, `console.log()` means: call the `log` method that belongs to the `console` object.

Sprint-2/1-key-errors/0.js

@@ -10,4 +10,5 @@ function capitalise(str) {
 }
 
 // =============> write your explanation here
+
 // =============> write your new code here