Sheffield | 26-ITP-Jan | Mahammad Osman | Sprint 1 | Coursework

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

@@ -4,3 +4,5 @@ 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
+//  = It assign the value of the variable count added to 1, it's called Incrementing 
+// Also Line 3, could be written as such   count++; according to doc

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

@@ -5,7 +5,12 @@ 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); 
+// I understood that charAt(0) gets the first character of the string. also I can concatenate strings with the + operator 
+// I can also use bracket notation/ Index access to get the first character of the string like this: 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 +17,7 @@ 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 ext = filePath.slice(filePath.lastIndexOf("."));
 
 // https://www.google.com/search?q=slice+mdn

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

@@ -7,3 +7,14 @@ 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
+
+console.log(num);
+
+// I understand that Math.random() generates a random number between 0 and 1, 
+// and multiplies it by the range (maximum - minimum + 1) to get a number in that range.
+// and then adds the minimum to shift the range to start from the minimum value 1 -> 100 rather than 0 -> 99.
+// finally, Math.floor() rounds the number down.
+
+// docs for Math.random() and Math.floor() I used:
+// https://www.google.com/search?q=Math.random+mdn
+// https://www.google.com/search?q=Math.floor+mdn

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

@@ -1,2 +1,3 @@
-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?
+// by simply commenting out the lines with //   the computer will ignore these lines and not run them

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

@@ -1,4 +1,13 @@
 // trying to create an age variable and then reassign the value by 1
 
-const age = 33;
+// const age = 33;
+// age = age + 1;
+
+// this code will throw an error because age is declared as a constant and we cannot reassign a new value to a constant variable
+
+// To fix this error, we can change the declaration of age from const to let
+
+let age = 33;
 age = age + 1;
+
+// Now the code will work without throwing an error, and the value of age will be updated to 34.

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

@@ -3,3 +3,5 @@
 
 console.log(`I was born in ${cityOfBirth}`);
 const cityOfBirth = "Bolton";
+
+// The error is that we are trying to use the variable cityOfBirth before it has been declared and assigned a value.

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

@@ -7,3 +7,7 @@ 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
+
+console.log(last4Digits);
+
+// The error is that cardNumber is a number and the slice method is a string method, so we cannot use slice on a number. 

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

@@ -1,2 +1,12 @@
 const 12HourClockTime = "20:53";
-const 24hourClockTime = "08:53";
+const 24hourClockTime = "08:53";
+
+
+
+console.log(12HourClockTime);
+console.log(24hourClockTime);
+
+// it throws a SyntaxError: Invalid or unexpected token because variable names cannot start with a number.
+// The error is that we are trying to assign a string value to a variable that starts with a number, which is not allowed in JavaScript.
+// Variable names cannot start with a number.
+

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

@@ -12,11 +12,30 @@ 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. The lines where a function call is made are:
+// Line 1: carPrice.replaceAll(",", "")
+// Line 2: priceAfterOneYear.replaceAll(",", "")
+// Line 3: Number(carPrice.replaceAll(",", ""))
+// Line 4: Number(priceAfterOneYear.replaceAll(",", ""))
+// Line 5: console.log(`The percentage change is ${percentageChange}`)
 
 // 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 is occurring in line 5, because it's missing a comma between the two arguments of the replaceAll method. 
+// to fix this problem, we can add a comma between the two arguments: priceAfterOneYear.replaceAll(",", "")
 
 // c) Identify all the lines that are variable reassignment statements
+// there are 2 variable reassignment statements in this file. The lines where a variable reassignment is made are:
+// Line 4 and 5 where we are reassigning new values to the variables 
+// carPrice and priceAfterOneYear after converting them to numbers and removing the commas.
 
 // d) Identify all the lines that are variable declarations
+// there are 4 variable declarations in this file. The lines where a variable declaration is made are:
+// Line 1: let carPrice = "10,000";
+// Line 2: let priceAfterOneYear = "8,543";
+// Line 6: const priceDifference = carPrice - priceAfterOneYear;
+// Line 7: const percentageChange = (priceDifference / carPrice) * 100;
 
 // e) Describe what the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression?
+// To remove the commas from the string carPrice and convert the resulting string to a number. 
+// Then, the Number function is used to convert the resulting string into a number data type,
+//  which can be used for mathematical operations.

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

@@ -12,14 +12,25 @@ 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.
 
 // b) How many function calls are there?
+// There is 1 function call, which is console.log(result).
 
 // c) Using documentation, explain what the expression movieLength % 60 represents
 // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Arithmetic_Operators
+// % is Remainder operator. In this case, movieLength % 60 gives us the number of seconds 
+// that are left after we have taken out all the full minutes from the movie length.
 
 // d) Interpret line 4, what does the expression assigned to totalMinutes mean?
+// calculates the total number of minutes in the movie length,
+// excluding the remaining seconds that are less than a full minute.
 
 // e) What do you think the variable result represents? Can you think of a better name for this variable?
+// The variable result represents the formatted time in hours, minutes, and seconds.
+// A better name for this variable could be movieFormattedTime.
 
 // f) Try experimenting with different values of movieLength. Will this code work for all values of movieLength? Explain your answer
+// This code will work for all non-negative integer values of movieLength.
+// However, if movieLength is a negative number, the result will be weird format with negative numbers.
+// Moreover, if movieLength is not an integer, the result will also be weird format with decimal numbers.

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

@@ -25,3 +25,12 @@ 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): removes the "p" from the string to get "399"
+// 3. const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0"): ensure it has at least 3 characters, resulting in "399" ,
+//  for example if the input was "99p", it would become "099" after padding, ensuring we can correctly extract pounds and pence in the next steps.
+// 4. const pounds = paddedPenceNumberString.substring(0, paddedPenceNumberString.length - 2): 
+// extracts the pounds part by taking the substring from the start to the length minus 2, resulting in "3"
+// 5. const pence = paddedPenceNumberString.substring(paddedPenceNumberString.length - 2).padEnd(2, "0"):
+//  extracts the pence part by taking the last two characters and pads it with trailing zeros if necessary, resulting in "99"
+// 6. console.log(`£${pounds}.${pence}`): 
+// outputs the final formatted price in pounds and pence, which is "£3.99"

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

@@ -11,8 +11,13 @@ In the Chrome console,
 invoke the function `alert` with an input string of `"Hello world!"`;
 
 What effect does calling the `alert` function have?
+An alert message displays in chrome, the content of the message is the webpage or the website says the string i typed in an alert way.
 
 Now try invoking the function `prompt` with a string input of `"What is your name?"` - store the return value of your call to `prompt` in an variable called `myName`.
 
 What effect does calling the `prompt` function have?
+It allows you to input a value in box the browser displays, in this example myName was assigned using =  with a value i inputted after running the code.
+
 What is the return value of `prompt`?
+The string you input in the field. but after looking more into it,
+there is an edge case where the user can click cancel in this situation the return value is null which means absences of value.

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

@@ -5,12 +5,27 @@ In this activity, we'll explore some additional concepts that you'll encounter i
 Open the Chrome devtools Console, type in `console.log` and then hit enter
 
 What output do you get?
+console.log
+ƒ log() { [native code] }
+ƒ stands for "function"
+[native code] part just means it's a function built in so we can't see the actual underlying JavaScript code for it.
 
 Now enter just `console` in the Console, what output do you get back?
+console
+console {debug: ƒ, error: ƒ, info: ƒ, log: ƒ, warn: ƒ, …}
+I think it gives a options of methods i can use with the object console.
 
 Try also entering `typeof console`
+typeof console
+'object'
+from the name i can understand that typeof tells you the variable type so for console its object type.
 
 Answer the following questions:
 
 What does `console` store?
+It stores a collection of methods.
+
 What does the syntax `console.log` or `console.assert` mean? In particular, what does the `.` mean?
+ It means that i want to use a method (e.g. `log` or `assert`) that belong to an object (e.g. `console`)
+ `.` is dot notation, it means get the method from the object.
+