diff --git a/Sprint-2/1-key-exercises/1-count.js b/Sprint-2/1-key-exercises/1-count.js index 117bcb2b6..d10099074 100644 --- a/Sprint-2/1-key-exercises/1-count.js +++ b/Sprint-2/1-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 + +// Line 3 takes the current value of count and adds 1 to it,and uses = to assign new value back to count,so the new value will be 1. diff --git a/Sprint-2/1-key-exercises/2-initials.js b/Sprint-2/1-key-exercises/2-initials.js index 964c9563c..6b9f1b03c 100644 --- a/Sprint-2/1-key-exercises/2-initials.js +++ b/Sprint-2/1-key-exercises/2-initials.js @@ -5,6 +5,8 @@ const 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. -const initials = ``; +const 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-2/1-key-exercises/3-paths.js b/Sprint-2/1-key-exercises/3-paths.js index ab90ebb28..cca4eeecc 100644 --- a/Sprint-2/1-key-exercises/3-paths.js +++ b/Sprint-2/1-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(".") + 1); -// https://www.google.com/search?q=slice+mdn \ No newline at end of file +// https://www.google.com/search?q=slice+mdn diff --git a/Sprint-2/1-key-exercises/4-random.js b/Sprint-2/1-key-exercises/4-random.js index 292f83aab..872b05e32 100644 --- a/Sprint-2/1-key-exercises/4-random.js +++ b/Sprint-2/1-key-exercises/4-random.js @@ -4,6 +4,19 @@ 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 represents a randomly generated whole number between 1 and 100. + // Try breaking down the expression and using documentation to explain what it means +// Math.random() generates a random decimal number greater than or equal to 0 and less than 1. Multiplying by 100 gives a number between 0 and up to, but not including 100. +// Math.floor() always rounds down and returns the largest integer less than or equal to a given number in this case between 0 and 99. Finally, adding 1 changes the range to 1–100. +// Math.floor(Math.random() * (maximum - minimum + 1)) +// Math.floor(Math.random() * (100 - 1 + 1)) +// Math.floor(Math.random() * 100) +// Math.random give any random number between 0 to 1 example 0.225 * 100 = 22.5 +// Math.floor rounds that number to a whole number so 22.5 will become 22 +// (22) + minimum +// 22 + 1 +// 23 + // 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 diff --git a/Sprint-2/2-mandatory-errors/0.js b/Sprint-2/2-mandatory-errors/0.js index cf6c5039f..044add7ac 100644 --- a/Sprint-2/2-mandatory-errors/0.js +++ b/Sprint-2/2-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? diff --git a/Sprint-2/2-mandatory-errors/1.js b/Sprint-2/2-mandatory-errors/1.js index 7a43cbea7..0eb59841e 100644 --- a/Sprint-2/2-mandatory-errors/1.js +++ b/Sprint-2/2-mandatory-errors/1.js @@ -1,4 +1,8 @@ // trying to create an age variable and then reassign the value by 1 -const age = 33; +//const age = 33; +//age = age + 1; + +let age = 33; age = age + 1; +console.log(age); diff --git a/Sprint-2/2-mandatory-errors/2.js b/Sprint-2/2-mandatory-errors/2.js index e09b89831..846e2891d 100644 --- a/Sprint-2/2-mandatory-errors/2.js +++ b/Sprint-2/2-mandatory-errors/2.js @@ -1,5 +1,9 @@ // Currently trying to print the string "I was born in Bolton" but it isn't working... // what's the error ? +//'cityOfBirth' cannot access before initialization + +// console.log(`I was born in ${cityOfBirth}`); +// const cityOfBirth = "Bolton"; -console.log(`I was born in ${cityOfBirth}`); const cityOfBirth = "Bolton"; +console.log(`I was born in ${cityOfBirth}`); diff --git a/Sprint-2/2-mandatory-errors/3.js b/Sprint-2/2-mandatory-errors/3.js index ec101884d..8f3400bab 100644 --- a/Sprint-2/2-mandatory-errors/3.js +++ b/Sprint-2/2-mandatory-errors/3.js @@ -1,9 +1,18 @@ -const cardNumber = 4533787178994213; +// const cardNumber = 4533787178994213; +// const last4Digits = cardNumber.slice(-4); + +const cardNumber = "4533787178994213"; const last4Digits = cardNumber.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 +//slice() not work with number + // Then run the code and see what error it gives. +//cardNumber.slice is not a function + // 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 diff --git a/Sprint-2/2-mandatory-errors/4.js b/Sprint-2/2-mandatory-errors/4.js index 5f86c730b..fc747a8ae 100644 --- a/Sprint-2/2-mandatory-errors/4.js +++ b/Sprint-2/2-mandatory-errors/4.js @@ -1,2 +1,5 @@ -const 12HourClockTime = "8:53pm"; -const 24hourClockTime = "20:53"; +// const 12HourClockTime = "8:53pm"; +// const 24hourClockTime = "20:53"; + +const ClockTime12Hour = "8:53pm"; +const ClockTime24Hour = "20:53"; diff --git a/Sprint-2/3-mandatory-interpret/1-percentage-change.js b/Sprint-2/3-mandatory-interpret/1-percentage-change.js index e24ecb8e1..138d3af64 100644 --- a/Sprint-2/3-mandatory-interpret/1-percentage-change.js +++ b/Sprint-2/3-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 +12,22 @@ 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 - +// 5 function calls +// -Number(carPrice.replaceAll(",", "")) +// -replaceAll(",", "") +// -Number(priceAfterOneYear.replaceAll("," "")) +// -replaceAll("," "") +// -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? - +// -Line 5 +// -missing ) after argument list +// -why: replaceAll() needs two arguments separated by a comma. +// -fix: by adding comma replaceAll(",", "") // c) Identify all the lines that are variable reassignment statements +// line 4 and 5 // d) Identify all the lines that are variable declarations - +// line 1,2,7 and 8 // e) Describe what the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression? +// -First removing the comma "10,000" +// -Second convert string into number 10000 diff --git a/Sprint-2/3-mandatory-interpret/2-time-format.js b/Sprint-2/3-mandatory-interpret/2-time-format.js index 47d239558..9377733c3 100644 --- a/Sprint-2/3-mandatory-interpret/2-time-format.js +++ b/Sprint-2/3-mandatory-interpret/2-time-format.js @@ -12,14 +12,17 @@ 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? - +// 6 // b) How many function calls are there? - +// 1 // c) Using documentation, explain what the expression movieLength % 60 represents // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Arithmetic_Operators - +// Remainder operator : calculates the remainder after dividing the movie length in seconds by 60 // d) Interpret line 4, what does the expression assigned to totalMinutes mean? +// It takes the remaining seconds away from the total movie length and divides by 60 to turn the seconds into minutes. // e) What do you think the variable result represents? Can you think of a better name for this variable? - +// - It represents the movie duration in hours, minutes, and seconds. +// - const movieDuration // f) Try experimenting with different values of movieLength. Will this code work for all values of movieLength? Explain your answer +// The code works with positive whole numbers for movieLength and changes them into hours, minutes, and seconds. Decimal or negative numbers may not give the correct result. diff --git a/Sprint-2/3-mandatory-interpret/3-to-pounds.js b/Sprint-2/3-mandatory-interpret/3-to-pounds.js index 60c9ace69..713bd67a2 100644 --- a/Sprint-2/3-mandatory-interpret/3-to-pounds.js +++ b/Sprint-2/3-mandatory-interpret/3-to-pounds.js @@ -2,13 +2,13 @@ const penceString = "399p"; const penceStringWithoutTrailingP = penceString.substring( 0, - penceString.length - 1 + penceString.length - 1, ); const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0"); const pounds = paddedPenceNumberString.substring( 0, - paddedPenceNumberString.length - 2 + paddedPenceNumberString.length - 2, ); const pence = paddedPenceNumberString @@ -25,3 +25,20 @@ console.log(`£${pounds}.${pence}`); // To begin, we can start with // 1. const penceString = "399p": initialises a string variable with the value "399p" + +// 1. const penceString = "399p" // Stores "399p" in a variable called penceString so the program can work with the price. +// 2. const penceStringWithoutTrailingP = penceString.substring( +// 0, +// penceString.length - 1); +// Removes the "p" from the end of "399p", leaving "399" +// 3. const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0"); +//Adds a "0" at the start if there are less than 3 digits. +// 4. const pounds = paddedPenceNumberString.substring( +// 0, +// paddedPenceNumberString.length - 2); //gets the digits before the last two to find the pounds. + +// 5. const pence = paddedPenceNumberString +// .substring(paddedPenceNumberString.length - 2) +// .padEnd(2, "0"); //gets the last two digits to find the pence. + +// 6. console.log(`£${pounds}.${pence}`); //Combines the pounds and pence and print the final price as £3.99 diff --git a/Sprint-2/4-stretch-explore/chrome.md b/Sprint-2/4-stretch-explore/chrome.md index 962580b82..c67f29356 100644 --- a/Sprint-2/4-stretch-explore/chrome.md +++ b/Sprint-2/4-stretch-explore/chrome.md @@ -9,7 +9,14 @@ In the Chrome console, invoke the function `alert` with one argument, the string What effect does calling the `alert` function have? +- A popup with chrome:/new-tab-page says "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? + +- A popup with chrome:/new-tab-page says "What is your name?" with a text box to type your name. + What is the return value of `prompt`? + +- "myname" which is the value that i entered. diff --git a/Sprint-2/4-stretch-explore/objects.md b/Sprint-2/4-stretch-explore/objects.md index 0216dee56..11726c63a 100644 --- a/Sprint-2/4-stretch-explore/objects.md +++ b/Sprint-2/4-stretch-explore/objects.md @@ -6,11 +6,23 @@ Open the Chrome devtools Console, type in `console.log` and then hit enter What output do you get? +- log() { [native code] } + Now enter just `console` in the Console, what output do you get back? +- console {debug: ƒ, error: ƒ, info: ƒ, log: ƒ, warn: ƒ, …} + Try also entering `typeof console` -Answer the following questions: +- 'object' + Answer the following questions: What does `console` store? + +- console stores different functions you can use to display or check information in the console. + What does the syntax `console.log` or `console.assert` mean? In particular, what does the `.` mean? + +- console.log() method accepts any value and outputs that the given value to the console. +- console.assert() takes a boolean first and displays the message only when the condition is false. +- "." means to access or call something inside this object either .log() or .assert() function. diff --git a/Sprint-2/README.md b/Sprint-2/README.md index 826253dfc..ec5623a22 100644 --- a/Sprint-2/README.md +++ b/Sprint-2/README.md @@ -12,7 +12,7 @@ This README will guide you through the different sections for this week. ## 1 Exercises -In this section, you'll have a short program and task. Some of the syntax may be unfamiliar - in this case, you'll need to look things up in documentation. +In this section, you'll have a short program and task. Some of the syntax may be unfamiliar - in this case, you'll need to look things up in documentation. https://developer.mozilla.org/en-US/docs/Web/JavaScript @@ -28,7 +28,7 @@ You must use documentation to make sense of anything unfamiliar - learning how t You can also use `console.log` to check the value of different variables in the code. -https://developer.mozilla.org/en-US/docs/Web/JavaScript +https://developer.mozilla.org/en-US/docs/Web/JavaScript ## 4 Explore - Stretch 💪