London | 25-ITP-Sep | Adnaan Abo | Sprint 1 | Coursework/sprint 1

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

@@ -1,6 +1,14 @@
 let count = 0;
 
-count = count + 1;
+count = count + 3;
 
 // 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 count variable by adding 1 to its current value. The = operator 
+// is used to assign the new value (count + 1) back to the count variable.
+// we can also say that the = operator is taking the value on the right side (count + 1) and storing it 
+// in the variable on the left side (count).
+
+// We can see the result of our code by logging the count variable to the console
+console.log(count);

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

@@ -5,7 +5,14 @@ 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 = ``;
+// You can use the .charAt() method of strings to get a character at a specific position in a string.
+// The first character is at position 0, the second at position 1, and so on.
+
+
+let initials = firstName.charAt(0) + middleName.charAt(0) + lastName.charAt(0);
 
 // https://www.google.com/search?q=get+first+character+of+string+mdn
 
+// Log the initials variable to the console
+console.log(initials);
+

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

@@ -17,7 +17,20 @@ 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 = ;
+// The dir part is everything before the base part
+// The ext part is everything after the last "." in the base part
+
+// You can use the .lastIndexOf() method of strings to find the position of the last occurrence of a specific character in a string.
+// For the dir part, you need to find the position of the last "/" in the filePath string.
+// For the ext part, you need to find the position of the last "." in the base string.
+
+const dir = filePath.slice(0, lastSlashIndex + 1);  // this will include the last "/"
+// if you don't want the last "/", use lastSlashIndex instead of lastSlashIndex + 1
+
+const ext = base.slice(base.lastIndexOf("."));  // this will include the "."
+// if you don't want the ".", use filePath.lastIndexOf(".") + 1 instead of filePath.lastIndexOf(".")
+
+console.log(`The dir part of ${filePath} is ${dir}`);
+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

@@ -4,6 +4,22 @@ const maximum = 100;
 const num = Math.floor(Math.random() * (maximum - minimum + 1)) + minimum;
 
 // In this exercise, you will need to work out what num represents?
+// num is a variable that stores a random integer between minimum and maximum.
+// the num variable is calculated using the Math.random() function, which generates a random floating-point number between 1 and 100.
+
 // Try breaking down the expression and using documentation to explain what it means
+// const num stores the result of the expression on the right-hand side of the equals sign
+// the = expression is used to assign a value to a variable
+// the expression (maximum - minimum + 1) calculates the range of numbers between minimum and maximum.
+// adding minimum shifts the range to start from the minimum value instead of 0.
+
 // It will help to think about the order in which expressions are evaluated
+// 1. (maximum - minimum + 1) is evaluated first, resulting in 100
+// 2. Math.random() is called, generating a random floating-point number between 0 (inclusive) and 1 (exclusive)
+// 3. The result of Math.random() is multiplied by the result of (maximum - minimum + 1), scaling the random number to the desired range    
+// 
+
 // Try logging the value of num and running the program several times to build an idea of what the program is doing
+// The running  the the program several times you can see that the program is generating a random number between 1 and 100.
+
+console.log(num);

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

@@ -1,2 +1,7 @@
-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? */
+
+// we can use // to comment out a single line
+// or we can use /* to start a multi-line comment
+// and end it with */
+

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

@@ -1,4 +1,9 @@
 // trying to create an age variable and then reassign the value by 1
 
-const age = 33;
+let age = 33;
 age = age + 1;
+
+// to reassign the value of age by 1 we need to use let instead of const
+
+console.log(age);
+

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

@@ -1,5 +1,7 @@
 // Currently trying to print the string "I was born in Bolton" but it isn't working...
 // what's the error ?
+// we need to declare the variable before we use it in the console.log statement
+
 
-console.log(`I was born in ${cityOfBirth}`);
 const cityOfBirth = "Bolton";
+console.log(`I was born in ${cityOfBirth}`);

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

@@ -1,9 +1,21 @@
 const cardNumber = 4533787178994213;
-const last4Digits = cardNumber.slice(-4);
+//const last4Digits = cardNumber.slice(-4);
 
 // The last4Digits variable should store the last 4 digits of cardNumber
+
 // However, the code isn't working
+// the error is that slice is not a function for numbers, it is a function for strings and arrays
+
 // Before running the code, make and explain a prediction about why the code won't work
+// My prediction is that the code will give an error because slice is not a function for numbers
+
 // Then run the code and see what error it gives.
+// typeError: cardNumber.slice is not a function
+
 // Consider: Why does it give this error? Is this what I predicted? If not, what's different?
+// It gives this error because slice is not a function for numbers, it is a function for strings and arrays. This is what I predicted.
+
 // Then try updating the expression last4Digits is assigned to, in order to get the correct value
+const cardNumberString = cardNumber.toString();
+const last4DigitsCorrected = cardNumberString.slice(-4);
+console.log(last4DigitsCorrected); // Should print 4213

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

@@ -1,2 +1,12 @@
-const 12HourClockTime = "20:53";
-const 24hourClockTime = "08:53";
+const a24HourClockTime = "20:53";
+const a12hourClockTime = "08:53";
+
+// The 12HourClockTime variable should store the time in 12-hour format
+// The 24hourClockTime variable should store the time in 24-hour format
+
+// However, the code isn't working
+// the error is that the variable names are not valid because they start with a number
+// Variable names cannot start with a number
+
+console.log(a24HourClockTime); // Should print: 08:53
+console.log(a12hourClockTime); // Should print: 20:53

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

@@ -2,7 +2,7 @@ let carPrice = "10,000";
 let priceAfterOneYear = "8,543";
 
 carPrice = Number(carPrice.replaceAll(",", ""));
-priceAfterOneYear = Number(priceAfterOneYear.replaceAll("," ""));
+priceAfterOneYear = Number(priceAfterOneYear.replaceAll(",", ""));
 
 const priceDifference = carPrice - priceAfterOneYear;
 const percentageChange = (priceDifference / carPrice) * 100;
@@ -12,11 +12,17 @@ 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 in this file, they are on lines 1, 2, 5, 6 and 9
 
 // 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?
+// the error was coming from line 5 there was a comma missing between the 2 quotations ("," "") by adding the comma the code was fixed and it worked as it should.
 
 // c) Identify all the lines that are variable reassignment statements
+// the variable reassignment statements are on lines 5 and 6
 
 // d) Identify all the lines that are variable declarations
+// the variable declaration statements are on lines 1, 2, 4, 7 and 8
 
 // e) Describe what the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression?
+/* the expression is taking the variable carPrice and replacing all the commas in the string with nothing and then converting 
+the string into a number so that it can be used in calculations.*/

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

@@ -1,4 +1,4 @@
-const movieLength = 8784; // length of movie in seconds
+const movieLength = 7784; // length of movie in seconds
 
 const remainingSeconds = movieLength % 60;
 const totalMinutes = (movieLength - remainingSeconds) / 60;
@@ -12,14 +12,22 @@ 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 6 variable declarations in this program. They are on lines 1, 3, 4, 6, 7 and 9
 
 // b) How many function calls are there?
+// there are 2 function calls in this program. They are on lines 9 and 10
 
 // 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 is using the modulus operator (%) to find the remainder when movieLength (8784) is divided by 60.
 
 // d) Interpret line 4, what does the expression assigned to totalMinutes mean?
+/* line 4 is calculating the total number of minutes in the movie by subtracting the remaining seconds from the total movie length in 
+seconds and then dividing that result by 60.*/
 
 // e) What do you think the variable result represents? Can you think of a better name for this variable?
+/* the variable result represents the total length of the movie in hours, minutes and seconds. A better name for this variable could 
+be movieDuration.*/
 
 // f) Try experimenting with different values of movieLength. Will this code work for all values of movieLength? Explain your answer
+// yes this code will work for all values of movieLength as long as the value is a non-negative integer representing the length of a movie in seconds.

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

@@ -1,21 +1,21 @@
-const penceString = "399p";
+const penceString = "1399p"; // stores the price in pence as a string with a trailing 'p'
 
 const penceStringWithoutTrailingP = penceString.substring(
   0,
   penceString.length - 1
-);
+);  // removes the trailing 'p' from the string to isolate the numeric part
 
 const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0");
 const pounds = paddedPenceNumberString.substring(
   0,
   paddedPenceNumberString.length - 2
-);
+);  // extracts the pounds part by taking all but the last two characters
 
 const pence = paddedPenceNumberString
-  .substring(paddedPenceNumberString.length - 2)
-  .padEnd(2, "0");
+  .substring(paddedPenceNumberString.length - 2)  // extracts the last two characters as the pence part
+  .padEnd(2, "0");  // ensures the pence part is two digits by padding with '0' if necessary
 
-console.log(`£${pounds}.${pence}`);
+console.log(`£${pounds}.${pence}`);  // outputs the formatted price in pounds and pence
 
 // This program takes a string representing a price in pence
 // The program then builds up a string representing the price in pounds