juneMonton · juneMonton · Dec 1, 2025 · Dec 1, 2025 · Dec 1, 2025 · Dec 16, 2025
diff --git a/Sprint-1/1-key-exercises/1-count.js b/Sprint-1/1-key-exercises/1-count.js
@@ -2,5 +2,8 @@ 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
+
+//line 3 is updating the value of the variable count to 'count+1
diff --git a/Sprint-1/1-key-exercises/2-initials.js b/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 = `${firstName.charAt(0)}${middleName.charAt(0)}${lastName.charAt(0)}`;
+console.log(initials);
 
 // https://www.google.com/search?q=get+first+character+of+string+mdn
 
diff --git a/Sprint-1/1-key-exercises/3-paths.js b/Sprint-1/1-key-exercises/3-paths.js
@@ -10,14 +10,19 @@
 // (All spaces in the "" line should be ignored. They are purely for formatting.)
 
 const filePath = "/Users/mitch/cyf/Module-JS1/week-1/interpret/file.txt";
-const lastSlashIndex = filePath.lastIndexOf("/");
-const base = filePath.slice(lastSlashIndex + 1);
+const lastSlashIndex = filePath.lastIndexOf("/");// result gives the index value until the last '/'
+const base = filePath.slice(lastSlashIndex + 1); // result will slice the 'filePath value with the number output from lastIndexOf
 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) ;
+const lastDotIndex=base.lastIndexOf(".");
+const ext = base.slice(lastDotIndex);
+
+console.log(dir);
+console.log(ext);
 
 // https://www.google.com/search?q=slice+mdn
diff --git a/Sprint-1/1-key-exercises/4-random.js b/Sprint-1/1-key-exercises/4-random.js
@@ -2,8 +2,15 @@ const minimum = 1;
 const maximum = 100;
 
 const num = Math.floor(Math.random() * (maximum - minimum + 1)) + minimum;
-
+console.log(num);
 // In this exercise, you will need to work out what num represents?
 // 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
+
+//(maximum - minimum + 1) this will give a result of 99+1
+//Math.random() will give a random number lesser 1
+//Math.floor(Math.random() * (maximum - minimum + 1)) this expression will remove the decimal point and round down the value
+//+ minimum this is the last part to be evaluated, it will add 1 to the first part
+
+//Answer: num will give a random value from 0 to 100
diff --git a/Sprint-1/2-mandatory-errors/0.js b/Sprint-1/2-mandatory-errors/0.js
@@ -1,2 +1,4 @@
-This is just an instruction for the first activity - but it is just for human consumption
-We don't want the computer to run these 2 lines - how can we solve this problem?
+/*This is just an instruction for the first activity - but it is just for human consumption
+We don't want the computer to run these 2 lines - how can we solve this problem?*/
+
+//I have commented the 2 lines since it is not meant for the computer to run
diff --git a/Sprint-1/2-mandatory-errors/1.js b/Sprint-1/2-mandatory-errors/1.js
@@ -2,3 +2,5 @@
 
 const age = 33;
 age = age + 1;
+
+// Age was assigned as a constant variable, it can't be reassigned. We can change it to let, let age=33;
diff --git a/Sprint-1/2-mandatory-errors/2.js b/Sprint-1/2-mandatory-errors/2.js
@@ -3,3 +3,5 @@
 
 console.log(`I was born in ${cityOfBirth}`);
 const cityOfBirth = "Bolton";
+
+//Because the cityOfBirth was not defined yet before printing it, there's nothing to print
diff --git a/Sprint-1/2-mandatory-errors/3.js b/Sprint-1/2-mandatory-errors/3.js
@@ -5,5 +5,12 @@ const last4Digits = cardNumber.slice(-4);
 // However, the code isn't working
 // Before running the code, make and explain a prediction about why the code won't work
 // 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?
+// Consider: Why does it give this error? Is this what I predicted? If not, what's different?-It gives an error because .slice is a string method and not for a number.
+
+
+
+
 // Then try updating the expression last4Digits is assigned to, in order to get the correct value
+
+// const cardNumber = 4533787178994213;
+// const last4Digits = cardNumber.slice(-4);
diff --git a/Sprint-1/2-mandatory-errors/4.js b/Sprint-1/2-mandatory-errors/4.js
@@ -1,2 +1,7 @@
 const 12HourClockTime = "20:53";
-const 24hourClockTime = "08:53";
+const 24hourClockTime = "08:53";
+
+//a variable can't start with a number
+
+// const twelveHourClockTime = "20:53";
+// const twentyFourHourClockTime = "08:53";
diff --git a/Sprint-1/3-mandatory-interpret/1-percentage-change.js b/Sprint-1/3-mandatory-interpret/1-percentage-change.js
@@ -13,10 +13,33 @@ console.log(`The percentage change is ${percentageChange}`);
 
 // 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.replaceAll()
+    line 4 Number()
+    line 5 priceAfterOneYear.replaceAll()
+    line 5 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's a syntax error in line 5, there's no comma in between arguments
+    it should be priceAfterOneYear = Number(priceAfterOneYear.replaceAll(",", ""));
+    */
+
+
 // c) Identify all the lines that are variable reassignment statements
 
+    /*There are 2 variable reassignments
+    line 4, carPrice = Number(carPrice.replaceAll(",", ""));
+    line 5, priceAfterOneYear = Number(priceAfterOneYear.replaceAll(",", ""));
+
 // d) Identify all the lines that are variable declarations
 
+    /*Variable Declarations are lines 1,2,7 and 8
+
 // e) Describe what the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression?
+
+    //It removes all the commas converting the string to a number so it can be used in the math operations
+
diff --git a/Sprint-1/3-mandatory-interpret/2-time-format.js b/Sprint-1/3-mandatory-interpret/2-time-format.js
@@ -13,13 +13,26 @@ console.log(result);
 
 // a) How many variable declarations are there in this program?
 
-// b) How many function calls are there?
+    /*
+    There are 6 variable declarations
+    const movieLength
+    const remainingSeconds
+    const totalMinutes
+    const remainingMinutes
+    const totalHours
+    const result
+    */
+
+// b) How many function calls are there?-There's only 1 function call
 
 // 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 represents modulo operator, using %60 helps you extract how many seconds remaining.
+
 // d) Interpret line 4, what does the expression assigned to totalMinutes mean?
+    //totalMinutes represents how many complete minutes fit inside the movie length.
 
-// e) What do you think the variable result represents? Can you think of a better name for this variable?
+// e) What do you think the variable result represents? Can you think of a better name for this variable?-the result variable formats the movie time to a string showing hours, minutes and seconds, it can be renamed to formattedTime
 
-// f) Try experimenting with different values of movieLength. Will this code work for all values of movieLength? Explain your answer
+// f) Try experimenting with different values of movieLength. Will this code work for all values of movieLength? Explain your answer-Yes as long as the movieLength value is positive
diff --git a/Sprint-1/3-mandatory-interpret/3-to-pounds.js b/Sprint-1/3-mandatory-interpret/3-to-pounds.js
@@ -1,19 +1,19 @@
 const penceString = "399p";
 
 const penceStringWithoutTrailingP = penceString.substring(
-  0,
+0,
   penceString.length - 1
-);
+);// will remove 'p' so the answer is 399
 
-const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0");
+const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0");//this won't do much for the given since it's already 3 numbers
 const pounds = paddedPenceNumberString.substring(
   0,
   paddedPenceNumberString.length - 2
-);
+);// this code will remove the first digit, 
 
 const pence = paddedPenceNumberString
   .substring(paddedPenceNumberString.length - 2)
-  .padEnd(2, "0");
+  .padEnd(2, "0");//this code will add '0' in front of the pence if it has 1 number
 
 console.log(`£${pounds}.${pence}`);
 
@@ -25,3 +25,39 @@ 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
+);
+:remove the trailing 'p' from the string.substring(0, penceString.length - 1) takes characters from index 0 up to (but not including) the last character.
+*/
+
+
+/*
+3. const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0");
+:Ensure the string has at least 3 characters by adding leading zeros if necessary.
+*/
+
+
+
+/*
+4. const pounds = paddedPenceNumberString.substring(
+  0,
+  paddedPenceNumberString.length - 2
+);
+: This will extract the first digit, the pounds portion
+*/
+
+/*
+5.const pence = paddedPenceNumberString
+  .substring(paddedPenceNumberString.length - 2)
+  .padEnd(2, "0");//this code will add '0' in front of the pence if it has 1 number
+: this code extracts the pence portion, makes sure the it has exactly 2 digits
+*/
+
+/*
+6. console.log(`£${pounds}.${pence}`);
+:prints the new formatted value of pounds and pence
+*/
diff --git a/Sprint-2/1-key-errors/0.js b/Sprint-2/1-key-errors/0.js
@@ -1,5 +1,6 @@
 // Predict and explain first...
 //  =============> write your prediction here
+//Function capitalise will make thes tring input first letter to Big case 
 
 // call the function capitalise with a string input
 // interpret the error message and figure out why an error is occurring
@@ -9,5 +10,8 @@ function capitalise(str) {
   return str;
 }
 
-// =============> write your explanation here
+// =============> write your explanation here : str has been declared in the function parameter and inside the function
 // =============> write your new code here
+function capitalise(str) {
+  return str `${str[0].toUpperCase()}${str.slice(1)}`;
+}
diff --git a/Sprint-2/1-key-errors/1.js b/Sprint-2/1-key-errors/1.js
@@ -1,7 +1,8 @@
 // Predict and explain first...
+//the code was supposed to convert a number input into percentage
 
 // Why will an error occur when this program runs?
-// =============> write your prediction here
+// =============> write your prediction here: An error will occur because "decimalNumber" has been redeclared inside the function 
 
 // Try playing computer with the example to work out what is going on
 
@@ -15,6 +16,11 @@ function convertToPercentage(decimalNumber) {
 console.log(decimalNumber);
 
 // =============> write your explanation here
+//a variable can only be declared once, and const value cannot be replaced
 
 // Finally, correct the code to fix the problem
 // =============> write your new code here
+function convertToPercentage(decimalNumber) {
+  return `${decimalNumber * 100}%`;
+}
+console.log(decimalNumber);
diff --git a/Sprint-2/1-key-errors/2.js b/Sprint-2/1-key-errors/2.js
@@ -1,20 +1,22 @@
 
 // Predict and explain first BEFORE you run any code...
-
+//this will not run because variables num are not declared
 // this function should square any number but instead we're going to get an error
 
-// =============> write your prediction of the error here
+// =============> write your prediction of the error here: num is not defined
 
 function square(3) {
     return num * num;
 }
 
-// =============> write the error message here
+// =============> write the error message here: " Illegal return statement"
 
-// =============> explain this error message here
+// =============> explain this error message here: The return is outside the function, Javascript is treating is at function since the parameter is a value and not an identifier that's why the return inside was not treated as a function
 
 // Finally, correct the code to fix the problem
 
 // =============> write your new code here
 
-
+function square(num) {
+    return num * num;
+}
diff --git a/Sprint-2/2-mandatory-debug/0.js b/Sprint-2/2-mandatory-debug/0.js
@@ -1,14 +1,19 @@
 // Predict and explain first...
 
-// =============> write your prediction here
+// =============> write your prediction here: the code block will display "The result of multiplying 10 and 32 is 320 "
 
 function multiply(a, b) {
   console.log(a * b);
 }
 
 console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);
 
-// =============> write your explanation here
+// =============> write your explanation here: my prediction is wrong as the first console.log displays nothing as it doesn't have values yet and console.log doesn't hold a value it only displays
 
 // Finally, correct the code to fix the problem
 //  =============> write your new code here
+function multiply(a, b) {
+  return a * b;
+}
+
+console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);
diff --git a/Sprint-2/2-mandatory-debug/1.js b/Sprint-2/2-mandatory-debug/1.js
@@ -1,5 +1,5 @@
 // Predict and explain first...
-//  =============> write your prediction here
+//  =============> write your prediction here: this will result to an error because return doesn't have anything to perform 
 
 function sum(a, b) {
   return;
@@ -8,6 +8,12 @@ function sum(a, b) {
 
 console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);
 
-// =============> write your explanation here
+// =============> write your explanation here: Operation a+b is after the return code, after return the function ends immediately
+
 // Finally, correct the code to fix the problem
 //  =============> write your new code here
+function sum(a, b) {
+  return a + b;
+}
+
+console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);
diff --git a/Sprint-2/2-mandatory-debug/2.js b/Sprint-2/2-mandatory-debug/2.js
@@ -1,7 +1,7 @@
 // Predict and explain first...
 
 // Predict the output of the following code:
-// =============> Write your prediction here
+// =============> Write your prediction here: it will always display that the last number of all input is 3
 
 const num = 103;
 
@@ -16,9 +16,17 @@ console.log(`The last digit of 806 is ${getLastDigit(806)}`);
 // Now run the code and compare the output to your prediction
 // =============> write the output here
 // Explain why the output is the way it is
-// =============> write your explanation here
+// =============> write your explanation here :num is declared as const, so num will always be 103 and last digit will always be 3
 // Finally, correct the code to fix the problem
 // =============> write your new code here
+function getLastDigit(num) {
+  return num.toString().slice(-1);
+}
+
+console.log(`The last digit of 42 is ${getLastDigit(42)}`);   // 2
+console.log(`The last digit of 105 is ${getLastDigit(105)}`); // 5
+console.log(`The last digit of 806 is ${getLastDigit(806)}`); // 6
+
 
 // This program should tell the user the last digit of each number.
 // Explain why getLastDigit is not working properly - correct the problem
diff --git a/Sprint-2/3-mandatory-implement/1-bmi.js b/Sprint-2/3-mandatory-implement/1-bmi.js
@@ -15,5 +15,6 @@
 // It should return their Body Mass Index to 1 decimal place
 
 function calculateBMI(weight, height) {
-    // return the BMI of someone based off their weight and height
-}
+    const bmi = weight / (height * height);   // divide weight by height squared
+    return bmi.toFixed(1);                    // round to 1 decimal place
+}
diff --git a/Sprint-2/3-mandatory-implement/2-cases.js b/Sprint-2/3-mandatory-implement/2-cases.js
@@ -14,3 +14,6 @@
 // You will need to come up with an appropriate name for the function
 // Use the MDN string documentation to help you find a solution
 // This might help https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/toUpperCase
+function toUpperSnakeCase(str) {
+    return str.toUpperCase().replace(/ /g, '_'); //.replace(/ /g, '_') → replaces all spaces with underscores (_).
+}
Original file line number	Diff line number	Diff line change
Expand Up		@@ -2,3 +2,5 @@

		const age = 33;
		age = age + 1;

		// Age was assigned as a constant variable, it can't be reassigned. We can change it to let, let age=33;
Original file line number	Diff line number	Diff line change
Expand Up		@@ -3,3 +3,5 @@

		console.log(`I was born in ${cityOfBirth}`);
		const cityOfBirth = "Bolton";

		//Because the cityOfBirth was not defined yet before printing it, there's nothing to print