London | 26-ITP-Jan | Abdul Moiz | Sprint 2 | Sprint 2

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

@@ -4,10 +4,20 @@
 // 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;
+// }
+
+// console.log(capitalise("lowercase"));
 
 // =============> write your explanation here
+// The error states str has already been declared. This is because str is the parameter and within the
+// function it is trying to declare a new variable with the same name using let.
+
 // =============> write your new code here
+function capitalise(str) {
+  return `${str[0].toUpperCase()}${str.slice(1)}`;
+}
+
+console.log(capitalise("lowercase"));

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

@@ -2,19 +2,30 @@
 
 // Why will an error occur when this program runs?
 // =============> write your prediction here
+// My prediction of the error is that nothing will be displayed because console.log isn't calling a function
+// it is just calling a variable that is not defined in this scope.
 
 // 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
+// The error occurs because the variable 'decimalNumber' is the parameter of the function
+// but it is being re-declared inside the function which causes a conflict.
 
 // 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

@@ -1,20 +1,26 @@
-
 // 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
+// Prediction of the error is that the function parameter is not valid.
+// It should be a variable name, not a number.
 
-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 there is an unexpected number in the function parameter list.
 
 // Finally, correct the code to fix the problem
 
 // =============> write your new code here
+function square(num) {
+  return num * num;
+}
 
-
+console.log(square(4)); // should print 16, does display correctly.

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

@@ -1,14 +1,22 @@
 // Predict and explain first...
 
 // =============> write your prediction here
+// The function multiply does not return any value, it only logs the result to the console.
 
-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
+// The function multiply does not return any value, it only logs the result to the console.
+// When we try to use the result of multiply(10, 32), it will be 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
+// The function sum does not return any value because of the misplaced semicolon after return.
 
-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 function sum has a return statement followed by a semicolon, which causes the function to return undefined.
+
 // 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 +2,39 @@
 
 // Predict the output of the following code:
 // =============> Write your prediction here
+// The function will always return '3' because it uses the global variable num instead of the input parameter.
 
 const num = 103;
 
-function getLastDigit() {
-  return num.toString().slice(-1);
-}
+// 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)}`);
+// 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
 // =============> write your explanation here
+// The function getLastDigit does not use its input parameter. Instead it always converts the global
+// variable num, which is 103 to a string and returns its last character which is '3'.
+
 // Finally, correct the code to fix the problem
 // =============> write your new code here
 
+function getLastDigit(number) {
+  return number.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

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

@@ -15,5 +15,11 @@
 // 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
-}
+  let heightSquared = height * height;
+  let bmi = weight / heightSquared;
+  return parseFloat(bmi.toFixed(1));
+}
+
+console.log(calculateBMI(70, 1.73));
+// Expected output: 23.4
+// Actual output: 23.4

Sprint-2/3-mandatory-implement/2-cases.js

@@ -14,3 +14,13 @@
 // 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(inputString) {
+  let upperCaseString = inputString.toUpperCase();
+  let upperSnakeCaseString = upperCaseString.replace(/ /g, "_");
+  return upperSnakeCaseString;
+}
+
+console.log(toUpperSnakeCase("lord of the rings"));
+// Expected output: "LORD_OF_THE_RINGS"
+// Actual output: "LORD_OF_THE_RINGS"

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

@@ -4,3 +4,26 @@
 // 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
+
+function toPounds(penceStringWithP) {
+  const penceStringWithoutTrailingP = penceStringWithP.substring(
+    0,
+    penceStringWithP.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("50p")); // Exp: £0.50, Acc: £0.50
+console.log(toPounds("399p")); // Exp: £3.99, Acc: £3.99
+console.log(toPounds("5p")); // Exp: £0.05, Acc: £0.05
+console.log(toPounds("12345p")); // Exp: £123.45, Acc: £123.45

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

@@ -11,24 +11,31 @@ function formatTimeDisplay(seconds) {
   return `${pad(totalHours)}:${pad(remainingMinutes)}:${pad(remainingSeconds)}`;
 }
 
+console.log(formatTimeDisplay(61));
+
 // 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?
 // =============> write your answer here
+// The pad function will be called 3 times
 
 // 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?
 // =============> write your answer here
+// The value assigned to num is 0
 
 // c) What is the return value of pad is called for the first time?
 // =============> write your answer here
+// The return value is "00"
 
 // 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 is 1 because the last call to pad is for the remaining seconds, which is 1 second.
 
 // 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 is "01" because the last call to pad is for the remaining seconds, which is 1 second.

Sprint-2/5-stretch-extend/format-time.js

@@ -2,11 +2,31 @@
 // 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.
 
+// function formatAs12HourClock(time) {
+//   const hours = Number(time.slice(0, 2));
+//   if (hours > 12) {
+//     return `${hours - 12}:00 pm`;
+//   }
+//   return `${time} am`;
+// }
+
+// Updated function:
 function formatAs12HourClock(time) {
   const hours = Number(time.slice(0, 2));
+  const minutes = time.slice(-2);
+
+  if (hours === 0) {
+    return `12:${minutes} am`;
+  }
+
+  if (hours === 12) {
+    return `12:${minutes} pm`;
+  }
+
   if (hours > 12) {
-    return `${hours - 12}:00 pm`;
+    return `${hours - 12}:${minutes} pm`;
   }
+
   return `${time} am`;
 }
 
@@ -23,3 +43,20 @@ console.assert(
   currentOutput2 === targetOutput2,
   `current output: ${currentOutput2}, target output: ${targetOutput2}`
 );
+
+// Morning times
+console.assert(formatAs12HourClock("01:00") === "01:00 am");
+console.assert(formatAs12HourClock("11:59") === "11:59 am");
+
+// Noon
+console.assert(formatAs12HourClock("12:00") === "12:00 pm");
+console.assert(formatAs12HourClock("12:30") === "12:30 pm");
+
+// Afternoon / evening
+console.assert(formatAs12HourClock("13:00") === "1:00 pm");
+console.assert(formatAs12HourClock("18:45") === "6:45 pm");
+console.assert(formatAs12HourClock("23:59") === "11:59 pm");
+
+// Midnight
+console.assert(formatAs12HourClock("00:00") === "12:00 am");
+console.assert(formatAs12HourClock("00:15") === "12:15 am");