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5 changes: 5 additions & 0 deletions Sprint-1/1-key-exercises/1-count.js
Original file line number Diff line number Diff line change
Expand Up @@ -4,3 +4,8 @@ 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 count variable by adding 1 to its current value.
The = opperator is an assignment opperator that assigns the result of the expression on the right (count+1) to the varibale on the left (count).
so, if count was 0 befor line 3 is excuted it will be 1 after line 3 is excuted.
And if it was 1 it will be 2 after line 3 is excuted.
Comment on lines +8 to +11
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Operation like count = count + 1 is very common in programming, and there is a programming term describing such operation.

Can you find out what one-word programming term describes the operation on line 3?

2 changes: 1 addition & 1 deletion Sprint-1/1-key-exercises/2-initials.js
Original file line number Diff line number Diff line change
Expand Up @@ -5,7 +5,7 @@ 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]);
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Why wrap the expression in a pair of parentheses? The syntax is still valid. It is just not a normal practice.


// https://www.google.com/search?q=get+first+character+of+string+mdn

7 changes: 4 additions & 3 deletions Sprint-1/1-key-exercises/3-paths.js
Original file line number Diff line number Diff line change
Expand Up @@ -17,7 +17,8 @@ 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}`);
const ext = filePath.slice (lastSlashIndex + 1);
console.log(`The ext part of ${filePath} is ${ext}`);
Comment on lines +22 to +23
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What is the expected value of ext (according to the illustration given on line 6-7)?

Does the code on line 23 output the expected value of "ext"?

// https://www.google.com/search?q=slice+mdn
2 changes: 2 additions & 0 deletions Sprint-1/1-key-exercises/4-random.js
Original file line number Diff line number Diff line change
Expand Up @@ -7,3 +7,5 @@ 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

num represents a random integer between the minimum and maximum values (inclusive).
4 changes: 3 additions & 1 deletion Sprint-1/2-mandatory-errors/0.js
Original file line number Diff line number Diff line change
@@ -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?
We don't want the computer to run these 2 lines - how can we solve this problem?

comment it out using // at the start of each line, or use /* at the start and */ at the end to comment out a block of code.
7 changes: 7 additions & 0 deletions Sprint-1/2-mandatory-errors/1.js
Original file line number Diff line number Diff line change
Expand Up @@ -2,3 +2,10 @@

const age = 33;
age = age + 1;
in this code we are trying to reassign the value of age variable by adding 1 to ageTrack.
However, this will result in an error because the age variable is diclared as a constant using the const keyword.
And in javascript, a variable decalred with const cannot be readdigned a new value afteer it has been intialised ,
so if we want to reassign the vlaue we have to use let instead.
let age = 33;
age = age +1;

5 changes: 3 additions & 2 deletions Sprint-1/2-mandatory-errors/2.js
Original file line number Diff line number Diff line change
@@ -1,5 +1,6 @@
// 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}`);

Because the const varibale is decalred after it is used in the console={.log} statement and it should be decalred befor to be executed.
9 changes: 8 additions & 1 deletion Sprint-1/2-mandatory-errors/3.js
Original file line number Diff line number Diff line change
@@ -1,9 +1,16 @@
const cardNumber = 4533787178994213;
const last4Digits = cardNumber.slice(-4);
const last4Digits = cardNumber .toString().slice(-4);
console.log(last4Digits);

// The last4Digits variable should store the last 4 digits of cardNumber
// 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?
// Then try updating the expression last4Digits is assigned to, in order to get the correct value

I exepected first that the .slice negative value (-4) will count from the beganning and drob of the first four Numbers.
When I run the code the error was that the cardNumber is not a function,
so I thought that I might need to turn the code into a function,
but when I checked an AI toolbar it showed that .slice is a methode that is used for string and array ,
so the card number should turned into a string by add .tostring after the card number and then use the .slice method to get the last 4 last4Digits.
4 changes: 3 additions & 1 deletion Sprint-1/2-mandatory-errors/4.js
Original file line number Diff line number Diff line change
@@ -1,2 +1,4 @@
const 12HourClockTime = "20:53";
const 24hourClockTime = "08:53";
const 24hourClockTime = "08:53";

In javascript variabl names should not start with a Number.
26 changes: 25 additions & 1 deletion Sprint-1/3-mandatory-interpret/1-percentage-change.js
Original file line number Diff line number Diff line change
Expand Up @@ -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;
Expand All @@ -12,11 +12,35 @@ 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 4 function calls in this File, they are in the following lines:
line 1: carPrice.replaceAll(",", "")
line 2: priceAfterOneYear.replaceAll(",", "")
line 3: Number(carPrice.replaceAll(",", ""))
line 4: Number(priceAfterOneYear.replaceAll(",", ""))
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There are more than 4 function calls.


// 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?

// c) Identify all the lines that are variable reassignment statements
there are 4 variables reassignment statements in this file, in the following lines:
line 1 = carPrice =
line 2 = priceAfterOneYear =
line 3 = carPrice = Number(carPrice.replaceAll(",", ""))
line 4 = priceAfterOneYear = Number(priceAfterOneYear.replaceAll(",", ""))




// d) Identify all the lines that are variable declarations
there are 2 variable declarations in this file , in :
line 1 : let carPrice =
line 2 : let priceFterOneYear =


// e) Describe what the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression?

the expression `Number(carPrice.replaceAll(",", ""))` is doing the following:
1. `carPrice.replaceAll(",", "")` removes all commas from the string value of `carPrice`.
2. `Number(...)` converts the resulting string (which no longer contains commas) into a number.

This is necessary because the original `carPrice` variable is a string with commas (e.g., "10,000"), and JavaScript cannot perform mathematical operations on strings with commas.
The purpose of this expression is to convert the formatted price string into a numeric value that can be used in calculations.
24 changes: 23 additions & 1 deletion Sprint-1/3-mandatory-interpret/2-time-format.js
Original file line number Diff line number Diff line change
Expand Up @@ -12,14 +12,36 @@ 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 programe they are in the following lines:

const movieLength = 8784; // length of movie in seconds

const remainingSeconds = movieLength % 60;
const totalMinutes = (movieLength - remainingSeconds) / 60;

const remainingMinutes = totalMinutes % 60;
const totalHours = (totalMinutes - remainingMinutes) / 60;

const result = `${totalHours}:${remainingMinutes}:${remainingSeconds}`;

// b) How many function calls are there?
there is 1 function call in this program and it is in the following line:

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
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Arithmetic_Operators

The expression `movieLength % 60` calculates the remainder when `movieLength` is divided by 60.
In this context, it gives the number of seconds that remain after converting the total seconds into minutes and hours.

// d) Interpret line 4, what does the expression assigned to totalMinutes mean?
The expression assigned to `totalMinutes` calculates the total number of minutes in `movieLength`
by subtracting the remaining seconds and dividing by 60.


// e) What do you think the variable result represents? Can you think of a better name for this variable?
variable result represents the formatted remaining movielength time in hours, minutes, and seconds (HH:MM:SS).
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Can you think of a better name for this variable?


// 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 asa long as it is a non- negative integers.
22 changes: 21 additions & 1 deletion Sprint-1/3-mandatory-interpret/3-to-pounds.js
Original file line number Diff line number Diff line change
Expand Up @@ -24,4 +24,24 @@ console.log(`£${pounds}.${pence}`);
// Try and describe the purpose / rationale behind each step

// To begin, we can start with
// 1. const penceString = "399p": initialises a string variable with the value "399p"
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 trailing "p" from the pence string, leaving just the numeric value "399".

3. const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0");
This line pads the numeric string with leading zeros to ensure it is at least 3 characters long, resulting in "0399".

4. const pounds = paddedPenceNumberString.substring(
0,
paddedPenceNumberString.length - 2
);
This line extracts the pounds part by taking all characters except the last two (which represent pence), resulting in "03".

5. const pence = paddedPenceNumberString
.substring(paddedPenceNumberString.length - 2)
.padEnd(2, "0");
This line extracts the last two characters (representing pence) and ensures they are exactly two digits long by padding with trailing zeros if necessary, resulting in "99".
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Could we expect this program to work as intended for any valid penceString if we deleted .padEnd(2, "0") from the code?
In other words, do we really need .padEnd(2, "0") in this script?


6. console.log(`£${pounds}.${pence}`);
This line logs the formatted price in pounds and pence, e.g., £03.99.