diff --git a/Sprint-1/1-key-exercises/1-count.js b/Sprint-1/1-key-exercises/1-count.js index 117bcb2b6..0a75b3002 100644 --- a/Sprint-1/1-key-exercises/1-count.js +++ b/Sprint-1/1-key-exercises/1-count.js @@ -4,3 +4,4 @@ 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 reassigns the value of the variable count. For this, the assignment operator = is used. The new value of count will be an expression of count + 1. diff --git a/Sprint-1/1-key-exercises/2-initials.js b/Sprint-1/1-key-exercises/2-initials.js index 47561f617..3e9e5b37c 100644 --- a/Sprint-1/1-key-exercises/2-initials.js +++ b/Sprint-1/1-key-exercises/2-initials.js @@ -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 = `${firstName.charAt(0)}${middleName.charAt(0)}${lastName.charAt(0)}`; // 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 index ab90ebb28..774c7a4fb 100644 --- a/Sprint-1/1-key-exercises/3-paths.js +++ b/Sprint-1/1-key-exercises/3-paths.js @@ -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, filePath.lastIndexOf("/",lastSlashIndex - 1)); +const ext = base.slice(base.lastIndexOf(".")); // https://www.google.com/search?q=slice+mdn \ No newline at end of file diff --git a/Sprint-1/1-key-exercises/4-random.js b/Sprint-1/1-key-exercises/4-random.js index 292f83aab..11c79c01e 100644 --- a/Sprint-1/1-key-exercises/4-random.js +++ b/Sprint-1/1-key-exercises/4-random.js @@ -7,3 +7,8 @@ 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 + +// First, maximum - minimum + 1 is calculated, so 100 - 1 + 1 equals 100. +// Then, a random fractional number between 0 and 1 is chosen(except 1), for example 0.3. +// Next, Math.random() * 100 gives 30. +// Math.floor rounds this number down to the nearest integer, and the final step adds 1, giving 31. \ No newline at end of file diff --git a/Sprint-1/2-mandatory-errors/0.js b/Sprint-1/2-mandatory-errors/0.js index cf6c5039f..65ad3030d 100644 --- a/Sprint-1/2-mandatory-errors/0.js +++ b/Sprint-1/2-mandatory-errors/0.js @@ -1,2 +1,2 @@ -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? \ No newline at end of file +//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? \ No newline at end of file diff --git a/Sprint-1/2-mandatory-errors/1.js b/Sprint-1/2-mandatory-errors/1.js index 7a43cbea7..031839b47 100644 --- a/Sprint-1/2-mandatory-errors/1.js +++ b/Sprint-1/2-mandatory-errors/1.js @@ -1,4 +1,4 @@ // trying to create an age variable and then reassign the value by 1 -const age = 33; +let age = 33; age = age + 1; diff --git a/Sprint-1/2-mandatory-errors/2.js b/Sprint-1/2-mandatory-errors/2.js index e09b89831..ae2731079 100644 --- a/Sprint-1/2-mandatory-errors/2.js +++ b/Sprint-1/2-mandatory-errors/2.js @@ -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}`); diff --git a/Sprint-1/2-mandatory-errors/3.js b/Sprint-1/2-mandatory-errors/3.js index ec101884d..fe5e7e8ad 100644 --- a/Sprint-1/2-mandatory-errors/3.js +++ b/Sprint-1/2-mandatory-errors/3.js @@ -1,4 +1,4 @@ -const cardNumber = 4533787178994213; +const cardNumber = '4533787178994213'; const last4Digits = cardNumber.slice(-4); // The last4Digits variable should store the last 4 digits of cardNumber diff --git a/Sprint-1/2-mandatory-errors/4.js b/Sprint-1/2-mandatory-errors/4.js index 21dad8c5d..549c84e63 100644 --- a/Sprint-1/2-mandatory-errors/4.js +++ b/Sprint-1/2-mandatory-errors/4.js @@ -1,2 +1,2 @@ -const 12HourClockTime = "20:53"; -const 24hourClockTime = "08:53"; \ No newline at end of file +const ClockTime12Hour = "20:53"; +const ClockTime24Hour = "08:53"; \ No newline at end of file diff --git a/Sprint-1/3-mandatory-interpret/1-percentage-change.js b/Sprint-1/3-mandatory-interpret/1-percentage-change.js index e24ecb8e1..0ef4fb967 100644 --- a/Sprint-1/3-mandatory-interpret/1-percentage-change.js +++ b/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 +// a) Lines 4,5,10 // 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? +// b) The error on the 5th line. Absence of , between arguments. // c) Identify all the lines that are variable reassignment statements +// c) Lines 4,5 // d) Identify all the lines that are variable declarations +// d) Lines 1,2,7,8 // e) Describe what the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression? +// e) This expression is removing the sign , from the carPrice variable then transforming the value from string to integer. +// The purpose of this expression is to convert the value of the variable into a form that is accessible for arithmetic calculations. \ No newline at end of file diff --git a/Sprint-1/3-mandatory-interpret/2-time-format.js b/Sprint-1/3-mandatory-interpret/2-time-format.js index 47d239558..e1899bf7f 100644 --- a/Sprint-1/3-mandatory-interpret/2-time-format.js +++ b/Sprint-1/3-mandatory-interpret/2-time-format.js @@ -12,14 +12,21 @@ 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? +// a) 6 // b) How many function calls are there? +// b) 1 // c) Using documentation, explain what the expression movieLength % 60 represents // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Arithmetic_Operators +// c) This expression shows the remaining part after dividing one number by another. +// This way we find out how many seconds are not enough to make up a full minute. // d) Interpret line 4, what does the expression assigned to totalMinutes mean? +// d) This way, we find out how many full minutes the film lasts. // e) What do you think the variable result represents? Can you think of a better name for this variable? +// e) This variable stores information about the exact length of the film (hours:minutes:seconds). I would call it “hoursMinutesSeconds” // f) Try experimenting with different values of movieLength. Will this code work for all values of movieLength? Explain your answer +// f) I tried several values where the length of the film is 0 or only a few minutes/seconds, etc. The code works in all the cases I tried and returns 0 as the result if the film, for example, is less than an hour long. \ No newline at end of file diff --git a/Sprint-1/3-mandatory-interpret/3-to-pounds.js b/Sprint-1/3-mandatory-interpret/3-to-pounds.js index 60c9ace69..800d9f215 100644 --- a/Sprint-1/3-mandatory-interpret/3-to-pounds.js +++ b/Sprint-1/3-mandatory-interpret/3-to-pounds.js @@ -1,12 +1,12 @@ const penceString = "399p"; -const penceStringWithoutTrailingP = penceString.substring( +const penceStringWithoutTrailingP = penceString.substring( // 399 0, penceString.length - 1 ); -const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0"); -const pounds = paddedPenceNumberString.substring( +const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0"); //399 +const pounds = paddedPenceNumberString.substring( //3 0, paddedPenceNumberString.length - 2 ); @@ -23,5 +23,10 @@ console.log(`£${pounds}.${pence}`); // You need to do a step-by-step breakdown of each line in this program // 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" + +//3. This line truncates the string by index, excluding the last character, without the letter p. +//8. This line is needed in case the variable length is shorter than 3 characters. If the variable value is less than 1 pound, calling the padStart() function guarantees that there are 3 characters so that we can later convert pence to the 0.00 format (we will add the decimal point later). +//9. saves the entire string except for the last 2 characters, i.e. the number of pounds +//14. saves the value of the last two characters, i.e. the number of pence +//18. this line outputs the final value in the standard format £0.00 + diff --git a/Sprint-1/4-stretch-explore/chrome.md b/Sprint-1/4-stretch-explore/chrome.md index e7dd5feaf..ad27bb53e 100644 --- a/Sprint-1/4-stretch-explore/chrome.md +++ b/Sprint-1/4-stretch-explore/chrome.md @@ -11,8 +11,11 @@ In the Chrome console, invoke the function `alert` with an input string of `"Hello world!"`; What effect does calling the `alert` function have? +Answer: A window pops up in the browser with the text “Hello world!” 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? +Answer: A window pops up in the browser with a text input field What is the return value of `prompt`? +Answer: undefined diff --git a/Sprint-1/4-stretch-explore/objects.md b/Sprint-1/4-stretch-explore/objects.md index 0216dee56..a0a9fa010 100644 --- a/Sprint-1/4-stretch-explore/objects.md +++ b/Sprint-1/4-stretch-explore/objects.md @@ -5,12 +5,17 @@ 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? +Answer: ƒ log() { [native code] } Now enter just `console` in the Console, what output do you get back? +Answer: console {debug: ƒ, error: ƒ, info: ƒ, log: ƒ, warn: ƒ, …} Try also entering `typeof console` +Answer:'object' Answer the following questions: What does `console` store? +Answer: Methods What does the syntax `console.log` or `console.assert` mean? In particular, what does the `.` mean? +Answer: `.` calls a method of an object.