Manchester | 26-ITP-Sept | Fatima Rouchi | Sprint 3 | Coursework/sprint 3

Sprint-3/1-key-errors/0.js

@@ -1,13 +1,25 @@
 // Predict and explain first...
-//  =============> write your prediction here
+//  =============>// I predict JavaScript will give a SyntaxError because str is declared twice in the function.
 
 // call the function capitalise with a string input
 // interpret the error message and figure out why an error is occurring
 
-function capitalise(str) {
+/*function capitalise(str) {
   let str = `${str[0].toUpperCase()}${str.slice(1)}`;
   return str;
 }
-
-// =============> write your explanation here
+capitalise("hello");*/
+/* =============>  The error happens because str is already the function's parameter.
+   let str tries to use the same name again, so JavaScript gives a SyntaxError.
+   The function stops before it can run. */
 // =============> write your new code here
+function capitalise(str) {
+  if (str === "") {
+    return "";
+  }
+
+  const result = `${str[0].toUpperCase()}${str.slice(1)}`;
+  return result;
+}
+
+console.log(`Result: "${capitalise("")}"`);

Sprint-3/1-key-errors/1.js

@@ -1,20 +1,29 @@
 // Predict and explain first...
 
 // Why will an error occur when this program runs?
-// =============> write your prediction here
+// =============>// I predict a SyntaxError because decimalNumber is declared as a parameter and then declared again with const.
 
 // Try playing computer with the example to work out what is going on
 
-function convertToPercentage(decimalNumber) {
+/*function convertToPercentage(decimalNumber) {
   const decimalNumber = 0.5;
   const percentage = `${decimalNumber * 100}%`;
 
   return percentage;
 }
 
-console.log(decimalNumber);
+console.log(decimalNumber);*/
 
-// =============> write your explanation here
+/* =============>  decimalNumber is already the function parameter.
+   const decimalNumber tries to declare the same name again inside the function,
+   so JavaScript gives a SyntaxError. */
 
 // 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-3/1-key-errors/2.js

@@ -1,20 +1,21 @@
-
 // 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
+// =============> // I predict a SyntaxError because 3 is a number, but a function parameter needs to be a name.
 
-function square(3) {
+/*function square(3) {
     return num * num;
 }
+*/
+// =============> SyntaxError: Unexpected number
 
-// =============> write the error message here
-
-// =============> explain this error message here
+// =============> The error happens because 3 is not a name. A parameter needs a name, like num.
 
 // Finally, correct the code to fix the problem
 
 // =============> write your new code here
-
-
+function square(num) {
+  return num * num;
+}
+console.log(square(3));

Sprint-3/2-mandatory-debug/0.js

@@ -1,14 +1,18 @@
 // Predict and explain first...
 
-// =============> write your prediction here
+// =============> I couldn't predict until I run the code
 
-function multiply(a, b) {
+/*function multiply(a, b) {
   console.log(a * b);
 }
 
-console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);
-
-// =============> write your explanation here
+console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);*/
 
+/* =============> The Terminal gives an answer of 320 but also says "The result of multiplying 10 and 32 is undefined"
+which makes me think that the function has no return so it gives back 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-3/2-mandatory-debug/1.js

@@ -1,13 +1,19 @@
 // Predict and explain first...
-//  =============> write your prediction here
+//  =============> I predict the code won't work because there's a ";" after return.
 
-function sum(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 sum is undefined because the semicolon after return ends it too early, 
+the function returns before adding a and b.*/
 // 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-3/2-mandatory-debug/2.js

@@ -1,24 +1,43 @@
 // Predict and explain first...
 
 // Predict the output of the following code:
-// =============> Write your prediction here
+// =============> I predict the result will be wrong because the num is set set on 103.
 
-const num = 103;
+/*const num = 103;
 
 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 806 is ${getLastDigit(806)}`);*/
 
 // Now run the code and compare the output to your prediction
-// =============> write the output here
+/* =============> the output:
+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 problem is that the function ignores the numbers passed to it, 
+ it always uses num, which is 103, so it returns 3 every time.*/
 // Finally, correct the code to fix the problem
 // =============> write your new code here
+/*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)}`);*/
 // This program should tell the user the last digit of each number.
 // Explain why getLastDigit is not working properly - correct the problem
+// In this case getLastDigit is not working because it's parameter is empty and not declared.
+// Here's the right code:
+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)}`);

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

@@ -15,5 +15,20 @@
 // It should return a string of their Body Mass Index to 1 decimal place
 
 function calculateBMI(weight, height) {
-  // return the BMI of someone based off their weight and height
+  return (weight / (height * height)).toFixed(1);
 }
+
+console.log(calculateBMI(52, 1.63));
+
+console.assert(
+  calculateBMI(70, 1.73) === "23.4",
+  "Expected BMI for 70kg and 1.73m to be 23.4",
+);
+console.assert(
+  calculateBMI(80, 1.8) === "24.7",
+  "Expected BMI for 80kg and 1.8m to be 24.7",
+);
+console.assert(
+  calculateBMI(60, 1.6) === "23.4",
+  "Expected BMI for 60kg and 1.6m to be 23.4",
+);

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

@@ -14,3 +14,17 @@
 // 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(words) {
+  return words.toUpperCase().trim().split(/\s+/).join("_");
+}
+
+console.log(toUpperSnakeCase("hello there"));
+
+console.assert(
+  toUpperSnakeCase("hello") === "HELLO",
+  'Expected "hello" to become "HELLO"',
+);
+console.assert(
+  toUpperSnakeCase("  hello   there  ") === "HELLO_THERE",
+  "Expected extra spaces to be trimmed and collapsed to one underscore",
+);

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

@@ -4,3 +4,20 @@
 // 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(penceString) {
+  const penceNumberString = String(penceString).replace(/p$/i, "");
+  const paddedPenceNumberString = penceNumberString.padStart(3, "0");
+
+  const pounds = paddedPenceNumberString.substring(
+    0,
+    paddedPenceNumberString.length - 2,
+  );
+
+  const pence = paddedPenceNumberString
+    .substring(paddedPenceNumberString.length - 2)
+    .padEnd(2, "0");
+  return `£${pounds}.${pence}`;
+}
+console.log(toPounds("599p"));
+console.log(toPounds("6p"));
+console.log(toPounds("2568p"));

Sprint-3/4-mandatory-interpret/time-format.js

@@ -14,25 +14,25 @@ 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
+// =============>Pad will be called 3 times: 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?
-// =============> write your answer here
+// =============> the first time pad is called, num gets the value of totalHours, which is 0.
 
 // c) What is the return value of pad when it is called for the first time?
-// =============> write your answer here
-
+// =============> the first time pad is called, it returns 00 because num is 0 and pad adds a zero in front.
 // 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 last time pad is called, num is 1 because there is 1 second left.
 
 // e) What is the return value of pad when it is called for the last time in this program?  Explain your answer
-// =============> write your answer here
+// =============>the last time pad is called, it returns 01 because num is 1 and pad adds a 0 in front.

Sprint-3/5-stretch-extend/format-time.js

@@ -3,23 +3,35 @@
 // 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 `${hours - 12}:00 pm`;
+  const [hoursString, minutesString = "00"] = time.split(":");
+  const hours = Number(hoursString);
+  const minutes = minutesString.padStart(2, "0");
+
+  let suffix = "am";
+  if (hours >= 12) {
+    suffix = "pm";
   }
-  return `${time} am`;
+
+  const formattedHours = String(hours % 12 || 12).padStart(2, "0");
+
+  return `${formattedHours}:${minutes} ${suffix}`;
 }
 
-const currentOutput = formatAs12HourClock("08:00");
-const targetOutput = "08:00 am";
-console.assert(
-  currentOutput === targetOutput,
-  `current output: ${currentOutput}, target output: ${targetOutput}`
-);
-
-const currentOutput2 = formatAs12HourClock("23:00");
-const targetOutput2 = "11:00 pm";
-console.assert(
-  currentOutput2 === targetOutput2,
-  `current output: ${currentOutput2}, target output: ${targetOutput2}`
-);
+function check(input, expected) {
+  const actual = formatAs12HourClock(input);
+
+  if (actual !== expected) {
+    console.error(`FAIL: ${input} -> ${actual} (expected ${expected})`);
+    process.exitCode = 1;
+  }
+}
+
+check("23:00", "11:00 pm");
+check("12:00", "12:00 pm");
+check("00:00", "12:00 am");
+check("08:00", "08:00 am");
+check("9:5", "09:05 am");
+
+if (!process.exitCode) {
+  console.log("All formatAs12HourClock tests passed.");
+}