diff --git a/Sprint-2/1-key-errors/0.js b/Sprint-2/1-key-errors/0.js index 653d6f5a0..c9c082180 100644 --- a/Sprint-2/1-key-errors/0.js +++ b/Sprint-2/1-key-errors/0.js @@ -1,5 +1,6 @@ // Predict and explain first... -// =============> write your prediction here +// =============> write your prediction here +// The code below is expected to show an error because the variable 'str' is declared twice. // call the function capitalise with a string input // interpret the error message and figure out why an error is occurring @@ -10,4 +11,11 @@ function capitalise(str) { } // =============> write your explanation here +// The error occurs because the variable 'str' is declared with 'let' twice in the same scope. +// The first declaration is a placeholder value, and the second is a variable declaration inside the function. // =============> write your new code here +// To fix this, we can remove the 'let' keyword from the second declaration of 'str'. +function capitalise(str) { + str = `${str[0].toUpperCase()}${str.slice(1)}`; + return str; +} diff --git a/Sprint-2/1-key-errors/1.js b/Sprint-2/1-key-errors/1.js index f2d56151f..ad2de91a3 100644 --- a/Sprint-2/1-key-errors/1.js +++ b/Sprint-2/1-key-errors/1.js @@ -2,9 +2,10 @@ // Why will an error occur when this program runs? // =============> write your prediction here +// An error will occur because the variable `decimalNumber` is declared twice, +// which is not allowed in JavaScript. // Try playing computer with the example to work out what is going on - function convertToPercentage(decimalNumber) { const decimalNumber = 0.5; const percentage = `${decimalNumber * 100}%`; @@ -15,6 +16,18 @@ function convertToPercentage(decimalNumber) { console.log(decimalNumber); // =============> write your explanation here +// The error occurs because the variable 'decimalNumber' is declared again +// inside the function 'convertToPercentage', although it has already been +// defined as a parameter. JavaScript does not allow redeclaring a parameter +// using const, let or var within the same scope. This causes a syntax error +// when the code is executed. // Finally, correct the code to fix the problem // =============> write your new code here + +function convertToPercentage(decimalNumber) { + const percentage = `${decimalNumber * 100}%`; + return percentage; +} + +console.log(convertToPercentage(0.5)); diff --git a/Sprint-2/1-key-errors/2.js b/Sprint-2/1-key-errors/2.js index aad57f7cf..85c761351 100644 --- a/Sprint-2/1-key-errors/2.js +++ b/Sprint-2/1-key-errors/2.js @@ -1,20 +1,34 @@ // Predict and explain first BEFORE you run any code... + // this function should square any number but instead we're going to get an error // =============> write your prediction of the error here +// It will show an error because function parameters must be variable names, +// not literal values. -function square(3) { - return num * num; -} +// function square(3) { + // return num * num; +// } // =============> write the error message here +// SyntaxError: Unexpected number // =============> explain this error message here +// The error message "SyntaxError: Unexpected number" indicates that +// the JavaScript interpreter encountered a number instead of a valid +// identifier like a variable name. +// In function declarations, parameters must be variable names and not +// literal values like 3. That is why using function square(3) caused a syntax error. // Finally, correct the code to fix the problem // =============> write your new code here +function square(num) { + return num * num; +} + +console.log(square(3)); diff --git a/Sprint-2/2-mandatory-debug/0.js b/Sprint-2/2-mandatory-debug/0.js index b27511b41..fec37a57b 100644 --- a/Sprint-2/2-mandatory-debug/0.js +++ b/Sprint-2/2-mandatory-debug/0.js @@ -1,6 +1,8 @@ // Predict and explain first... // =============> write your prediction here +//The code will be undefined because the "console.log(a * b)" function +// will not return a value, rather it will only log a result. function multiply(a, b) { console.log(a * b); @@ -9,6 +11,17 @@ function multiply(a, b) { console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`); // =============> write your explanation here +// The `multiply` function is designed to log the product of `a` and `b` +// to the console, but it does not return any value. +// When `multiply(10, 32)` is used inside the template string, +// it shows `undefined` because the function does not return anything. +// As a result, the console will first display 320 from inside the function, +// and then print; "The result of multiplying 10 and 32 is undefined". // Finally, correct the code to fix the problem // =============> write your new code here +function multiply(a, b) { + return a * b; +} + +console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`); \ No newline at end of file diff --git a/Sprint-2/2-mandatory-debug/1.js b/Sprint-2/2-mandatory-debug/1.js index 37cedfbcf..834cf11ae 100644 --- a/Sprint-2/2-mandatory-debug/1.js +++ b/Sprint-2/2-mandatory-debug/1.js @@ -9,5 +9,15 @@ function sum(a, b) { console.log(`The sum of 10 and 32 is ${sum(10, 32)}`); // =============> write your explanation here +/// The code is expected to return undefined because the return statement +// is placed before the actual addition operation. The function `sum` is +// defined to take two parameters, `a` and `b`, but it does not return their +// sum due to the misplaced semicolon after the `return` statement. + // Finally, correct the code to fix the problem // =============> write your new code here +function sum(a, b) { + return a + b; +} + +console.log(`The sum of 10 and 32 is ${sum(10, 32)}`); diff --git a/Sprint-2/2-mandatory-debug/2.js b/Sprint-2/2-mandatory-debug/2.js index 57d3f5dc3..4f3b2f95e 100644 --- a/Sprint-2/2-mandatory-debug/2.js +++ b/Sprint-2/2-mandatory-debug/2.js @@ -15,10 +15,28 @@ console.log(`The last digit of 806 is ${getLastDigit(806)}`); // Now run the code and compare the output to your prediction // =============> write the output here +// The last digit of 42 is 3 +// The last digit of 105 is 3 +// The last digit of 806 is 3 + // Explain why the output is the way it is // =============> write your explanation here +// The function `getLastDigit` does not accept any arguments. +// It always uses the constant `num` defined at the top, which is 103. +// Therefore, no matter what number is passed in the `console.log`, +// the function always returns the last digit of 103 ("3"). +// `getLastDigit` passes a value that is ignored since the function +// takes no parameters and always uses the fixed variable num = 103. + // Finally, correct the code to fix the problem // =============> write your new code here +function getLastDigit(num) { + return num.toString().slice(-1); +} + +console.log(`The last digit of 42 is ${getLastDigit(42)}`); +console.log(`The last digit of 105 is ${getLastDigit(105)}`); +console.log(`The last digit of 806 is ${getLastDigit(806)}`); // This program should tell the user the last digit of each number. // Explain why getLastDigit is not working properly - correct the problem diff --git a/Sprint-2/3-mandatory-implement/1-bmi.js b/Sprint-2/3-mandatory-implement/1-bmi.js index 17b1cbde1..5cf486f66 100644 --- a/Sprint-2/3-mandatory-implement/1-bmi.js +++ b/Sprint-2/3-mandatory-implement/1-bmi.js @@ -1,19 +1,26 @@ // Below are the steps for how BMI is calculated -// The BMI calculation divides an adult's weight in kilograms (kg) by their height in metres (m) squared. +// The BMI calculation divides an adult's weight in kilograms (kg) +// by their height in metres (m) squared. -// For example, if you weigh 70kg (around 11 stone) and are 1.73m (around 5 feet 8 inches) tall, you work out your BMI by: +// For example, if you weigh 70kg (around 11 stone) and are 1.73m +// (around 5 feet 8 inches) tall, you work out your BMI by: // squaring your height: 1.73 x 1.73 = 2.99 // dividing 70 by 2.99 = 23.41 // Your result will be displayed to 1 decimal place, for example 23.4. -// You will need to implement a function that calculates the BMI of someone based off their weight and height +// You will need to implement a function that calculates the BMI of someone +// based off their weight and height // Given someone's weight in kg and height in metres // Then when we call this function with the weight and height // It should return their Body Mass Index to 1 decimal place function calculateBMI(weight, height) { - // return the BMI of someone based off their weight and height -} \ No newline at end of file +// return the BMI of someone based off their weight and height + const BMI = weight / (height * height); + return Number(BMI.toFixed(1)); +} + +console.log(calculateBMI(70, 1.73)); diff --git a/Sprint-2/3-mandatory-implement/2-cases.js b/Sprint-2/3-mandatory-implement/2-cases.js index 5b0ef77ad..6d02719a0 100644 --- a/Sprint-2/3-mandatory-implement/2-cases.js +++ b/Sprint-2/3-mandatory-implement/2-cases.js @@ -14,3 +14,10 @@ // You will need to come up with an appropriate name for the function // Use the MDN string documentation to help you find a solution // This might help https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/toUpperCase + +function toUpperSnakeCase(input) { + return input.toUpperCase().replaceAll(" ", "_"); +} + +console.log(toUpperSnakeCase("hello there")); +console.log(toUpperSnakeCase("lord of the rings")); diff --git a/Sprint-2/3-mandatory-implement/3-to-pounds.js b/Sprint-2/3-mandatory-implement/3-to-pounds.js index 6265a1a70..f252adf89 100644 --- a/Sprint-2/3-mandatory-implement/3-to-pounds.js +++ b/Sprint-2/3-mandatory-implement/3-to-pounds.js @@ -4,3 +4,27 @@ // You will need to declare a function called toPounds with an appropriately named parameter. // You should call this function a number of times to check it works for different inputs + +// This function converts a string like "399p" into a formatted pounds and pence amount like "£3.99" + +function toPounds(penceString) { + + const penceStringWithoutTrailingP = penceString + .substring(0, penceString.length - 1); + + const paddedPenceNumberString = + penceStringWithoutTrailingP.padStart(3, "0"); + + const pounds = paddedPenceNumberString + .substring(0, paddedPenceNumberString.length - 2); + + const pence = paddedPenceNumberString + .substring(paddedPenceNumberString.length - 2); + + return `£${pounds}.${pence}`; +} +console.log(toPounds("399p")); +console.log(toPounds("99p")); +console.log(toPounds("5p")); +console.log(toPounds("1399p")); +console.log(toPounds("0p")); diff --git a/Sprint-2/4-mandatory-interpret/time-format.js b/Sprint-2/4-mandatory-interpret/time-format.js index 7c98eb0e8..5d02f518b 100644 --- a/Sprint-2/4-mandatory-interpret/time-format.js +++ b/Sprint-2/4-mandatory-interpret/time-format.js @@ -11,24 +11,45 @@ function formatTimeDisplay(seconds) { return `${pad(totalHours)}:${pad(remainingMinutes)}:${pad(remainingSeconds)}`; } -// You will need to play computer with this example - use the Python Visualiser https://pythontutor.com/visualize.html#mode=edit +// You will need to play computer with this example - use the +// Python Visualiser https://pythontutor.com/visualize.html#mode=edit // to help you answer these questions // Questions -// a) When formatTimeDisplay is called how many times will pad be called? +// a) When formatTimeDisplay is called how many +// times will pad be called? // =============> write your answer here +// 3 times. It is called once for hours, +// once for minutes and once for seconds. // Call formatTimeDisplay with an input of 61, now answer the following: -// b) What is the value assigned to num when pad is called for the first time? +// b) What is the value assigned to num when +// pad is called for the first time? // =============> write your answer here +// The value assigned to num when pad is +// called for the first time is 0. // c) What is the return value of pad is called for the first time? // =============> write your answer here +// The return value of pad when called for the first time is "00". +// This is because it pads the number 0 with leading zeros to +// ensure it has a length of 2 characters. -// d) What is the value assigned to num when pad is called for the last time in this program? Explain your answer +// d) What is the value assigned to num when pad +// is called for the last time in this program? Explain your answer // =============> write your answer here +// The value assigned to num when pad is called for the last time is 1. +// This is because the last call to pad is for the remaining seconds +// which is 61 % 60 = 1. -// e) What is the return value assigned to num when pad is called for the last time in this program? Explain your answer +// e) What is the return value assigned to num when +// pad is called for the last time in this program? +// Explain your answer // =============> write your answer here +// The return value assigned to num when pad is called for +// the last time is "01". +// This is because it applies .padStart(2, "0"), which returns +// a two character string, with a leading zero to ensure +// it has a minimum length of 2. diff --git a/Sprint-2/5-stretch-extend/format-time.js b/Sprint-2/5-stretch-extend/format-time.js index 32a32e66b..b08552999 100644 --- a/Sprint-2/5-stretch-extend/format-time.js +++ b/Sprint-2/5-stretch-extend/format-time.js @@ -1,6 +1,8 @@ // This is the latest solution to the problem from the prep. // Make sure to do the prep before you do the coursework -// Your task is to write tests for as many different groups of input data or edge cases as you can, and fix any bugs you find. +// Your task is to write tests for as many different groups of +// input data or edge cases as you can, and fix any bugs you find. + function formatAs12HourClock(time) { const hours = Number(time.slice(0, 2)); @@ -23,3 +25,27 @@ console.assert( currentOutput2 === targetOutput2, `current output: ${currentOutput2}, target output: ${targetOutput2}` ); + +// +function formatAs12HourClock(time) { + const [hourStr, minutes] = time.split(":"); + const hours = Number(hourStr); + + if (hours === 0) { + return `12:${minutes} am`; // Midnight + } + if (hours === 12) { + return `12:${minutes} pm`; // Noon + } + if (hours > 12) { + return `${String(hours - 12).padStart(2, "0")}:${minutes} pm`; + } + return `${time} am`; // Morning +} + +// Test cases +console.log(formatAs12HourClock("08:00")); +console.log(formatAs12HourClock("23:00")); +console.log(formatAs12HourClock("00:30")); +console.log(formatAs12HourClock("12:45")); +console.log(formatAs12HourClock("13:15"));