Birmingham | 25-ITP-Sep | Joy Opachavalit | Sprint 2 | coursework/sprint-2

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

@@ -1,13 +1,21 @@
 // Predict and explain first...
 //  =============> write your prediction here
+// PREDICTION: There will be a SyntaxError because 'str' is declared twice - once as parameter, once as variable
 
 // call the function capitalise with a string input
 // interpret the error message and figure out why an error is occurring
 
-function capitalise(str) {
-  let str = `${str[0].toUpperCase()}${str.slice(1)}`;
-  return str;
-}
+// function capitalise(str) {
+//   let str = `${str[0].toUpperCase()}${str.slice(1)}`;
+//   return str;
+// }
 
 // =============> write your explanation here
+// 1. Cannot redeclare 'str' with 'let' inside function - it's already the parameter name
+// 2. 'explain' is not defined - should be a string literal
+console.log(capitalise("hello")); // Test the function
 // =============> write your new code here
+function capitalise(str) {
+  let capitalised = `${str[0].toUpperCase()}${str.slice(1)}`;
+  return capitalised;
+}

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

@@ -2,19 +2,27 @@
 
 // Why will an error occur when this program runs?
 // =============> write your prediction here
+// PREDICTION: There will be a SyntaxError because 'decimalNumber' is declared twice - once as parameter, once as variable
 
 // Try playing computer with the example to work out what is going on
 
-function convertToPercentage(decimalNumber) {
-  const decimalNumber = 0.5;
-  const percentage = `${decimalNumber * 100}%`;
+// function convertToPercentage(decimalNumber) {
+//   const decimalNumber = 0.5;
+//   const percentage = `${decimalNumber * 100}%`;
 
-  return percentage;
-}
+//   return percentage;
+// }
 
-console.log(decimalNumber);
+// console.log(decimalNumber);
 
 // =============> write your explanation here
-
+// Cannot redeclare 'decimalNumber' with 'const' inside function - it's already the parameter name
 // 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));

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

@@ -4,17 +4,23 @@
 // this function should square any number but instead we're going to get an error
 
 // =============> write your prediction of the error here
+// PREDICTION: There will be a SyntaxError because '3' is not a valid parameter name
 
-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 indicates that the function parameter is not valid because '3' is a number literal, not a variable name.
 
 // Finally, correct the code to fix the problem
 
 // =============> write your new code here
+function square(num) {
+    return num * num;
+}
 
-
+console.log(square(5)); // Test the function

Sprint-2/2-mandatory-debug/0.js

@@ -1,14 +1,22 @@
 // Predict and explain first...
 
 // =============> write your prediction here
+// PREDICTION: The function will log the result of the multiplication, but the template literal will not include the result because multiply() does not return a value.
 
-function multiply(a, b) {
-  console.log(a * b);
-}
+// function multiply(a, b) {
+//   console.log(a * b);
+// }
 
-console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);
+// console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);
 
 // =============> write your explanation here
 
+// EXPLANATION: The multiply function logs the product of a and b, but it does not return any value. When we try to use multiply(10, 32) inside the template literal, it evaluates to undefined because there is no return statement in the function. Therefore, the output will be "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)}`);

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

@@ -1,13 +1,21 @@
 // Predict and explain first...
 //  =============> write your prediction here
+// PREDICTION: The function will not return the sum because the return statement is placed before the actual addition operation.
 
-function sum(a, b) {
-  return;
-  a + b;
-}
+// function sum(a, b) {
+//   return;
+//   a + b;
+// }
 
-console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);
+// console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);
 
 // =============> write your explanation here
+// The return statement is placed before the addition operation, so the function will return undefined instead of the sum.
+
 // 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)}`);

Sprint-2/2-mandatory-debug/2.js

@@ -2,23 +2,38 @@
 
 // Predict the output of the following code:
 // =============> Write your prediction here
+// PREDICTION: The function will log the last digit of the number passed to it, but it will not work as intended because the num variable is defined outside the function and is not being passed as an argument.
 
-const num = 103;
 
-function getLastDigit() {
-  return num.toString().slice(-1);
-}
+// const num = 103;
 
-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)}`);
+// function getLastDigit() {
+//   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)}`);
 
 // 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
+// The output is not as expected because the getLastDigit function is not using the argument passed to it. Instead, it is using the num variable defined outside the function, which is not being updated with the new values.
 // =============> write your explanation here
+// The getLastDigit function should take a number as an argument and return the last digit of that number. However, it is currently using the num variable defined outside the function, which is not being updated with the new values passed to the function.
 // 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
+// The getLastDigit function should take a number as an argument and return the last digit of that number. However, it is currently using the num variable defined outside the function, which is not being updated with the new values passed to the function.

Sprint-2/3-mandatory-implement/1-bmi.js

@@ -16,4 +16,7 @@
 
 function calculateBMI(weight, height) {
     // return the BMI of someone based off their weight and height
-}
+    const bmi = weight / (height * height);
+    return bmi.toFixed(1);
+}
+console.log(calculateBMI(70, 1.73)); // should return 23.4

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(str) {
+    // convert the string to UPPER_SNAKE_CASE
+    return str.toUpperCase().replaceAll(" ", "_");
+}
+console.log(toUpperSnakeCase("hello there"));
+console.log(toUpperSnakeCase("lord of the rings"));

Sprint-2/3-mandatory-implement/3-to-pounds.js

@@ -4,3 +4,50 @@
 // 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
+// const penceString = "399p";
+
+// 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)
+//   .padEnd(2, "0");
+
+
+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)
+      .padEnd(2, "0");
+    return `£${pounds}.${pence}`;
+}
+console.log(toPounds("399p"));
+console.log(toPounds("5p"))
+console.log(toPounds("007p")); // leading zeroes handled -> £0.07
+// Edge cases and inputs this function does not handle well (demonstration)
+// 1) Missing trailing 'p' – the current implementation will drop the last character,
+//    so "399" is treated like "39" and becomes £0.39 (not what we want)
+console.log(toPounds("399"));
+
+// 2) Different trailing character – the function does not validate the trailing 'p',
+//    it simply removes the last character. "399P" still returns £3.99
+console.log(toPounds("399P"));
+
+// This program takes a string representing a price in pence
+// The program then builds up a string representing the price in pounds
+
+// 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"

Sprint-2/4-mandatory-interpret/time-format.js

@@ -18,17 +18,23 @@ function formatTimeDisplay(seconds) {
 
 // a) When formatTimeDisplay is called how many times will pad be called?
 // =============> write your answer here
+// pad will be called 3 times, once for each of totalHours, remainingMinutes, and remainingSeconds.
 
 // Call formatTimeDisplay with an input of 61, now answer the following:
+console.log(formatTimeDisplay(61));
 
 // 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, which is the value of totalHours.
 
 // 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", which is the string representation of totalHours padded to 2 digits.
 
 // 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, which is the value of remainingSeconds. This is because 61 seconds has 1 remaining second after accounting for the full minute.
 
 // 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 of pad when called for the last time is "01", which is the string representation of remainingSeconds padded to 2 digits.