ZA-ITP-May-2025 | Christian Mayamba | Module-Structuring and Testing Data | Week 2

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

@@ -1,5 +1,7 @@
 // Predict and explain first...
-//  =============> write your prediction here
+//  =============> The function capitalise is trying to take a string input,
+// convert the first characater to uppercase and extract characters from
+// the second to the end of the string.
 
 // call the function capitalise with a string input
 // interpret the error message and figure out why an error is occurring
@@ -9,5 +11,16 @@ function capitalise(str) {
   return str;
 }
 
-// =============> write your explanation here
-// =============> write your new code here
+capitalise("hello");
+
+// =============> The error "Identifier 'str' has already been declared" is occuring
+// because the variable `str` is being declared twice in the function.
+
+// =============> This is my new code:
+
+function capitalise(str) {
+  let name = `${str[0].toUpperCase()}${str.slice(1)}`;
+  return name;
+}
+
+capitalise("hello");

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

@@ -1,7 +1,9 @@
 // Predict and explain first...
 
 // Why will an error occur when this program runs?
-// =============> write your prediction here
+// =============> My prediction is that the code will not give an error,
+// but it will be only giving 50% as a result when the function is called,
+// because the variable 'decimal number' is assigned the value of 0.5.
 
 // Try playing computer with the example to work out what is going on
 
@@ -14,7 +16,17 @@ function convertToPercentage(decimalNumber) {
 
 console.log(decimalNumber);
 
-// =============> write your explanation here
+// =============> The error "Identifier 'decimalNumber' has already been declared" is occurring
+// because the variable `decimalNumber` is being declared twice in the function.
+// And console.log cannot access the variable `decimalNumber` because of its scope.
 
 // Finally, correct the code to fix the problem
-// =============> write your new code here
+// =============> Here's my code:
+
+function convertToPercentage(decimalNumber) {
+  const percentage = `${decimalNumber * 100}%`;
+
+  return percentage;
+}
+
+console.log(convertToPercentage(0.7));

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

@@ -3,18 +3,22 @@
 
 // this function should square any number but instead we're going to get an error
 
-// =============> write your prediction of the error here
+// =============> The 'num' variable is not defined in the function scope,
+// so when we try to use it, it will throw an error.
 
 function square(3) {
     return num * num;
 }
 
-// =============> write the error message here
+// =============> The error is "SyntaxError: Unexpected number"
 
-// =============> explain this error message here
+// =============> The number '3" is used where it shouldn't be, as a parameter.
 
 // Finally, correct the code to fix the problem
 
-// =============> write your new code here
+// =============> write your new code here:
+function square(num) {
+    return num * num;
+}
 
 

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

@@ -1,14 +1,21 @@
 // Predict and explain first...
 
-// =============> write your prediction here
+// =============> The code won't run because the function `multiply`
+// is not making any calculation and it is not returning any value.
 
 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
+// =============> The result of multiplying 10 and 32 is undefined because
+// 'multiply' has not been properly defined to return a value.
 
 // Finally, correct the code to fix the problem
-//  =============> write your new code here
+//  =============> Here's the new code:
+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

@@ -1,5 +1,5 @@
 // Predict and explain first...
-//  =============> write your prediction here
+//  =============> The syntax of the function `sum` is incorrect.
 
 function sum(a, b) {
   return;
@@ -8,6 +8,12 @@ function sum(a, b) {
 
 console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);
 
-// =============> write your explanation here
+// =============> "a + b" should be on the same line as the return statement.
+
 // Finally, correct the code to fix the problem
-//  =============> write your new code here
+//  =============> Here's the new code:
+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

@@ -1,7 +1,8 @@
 // Predict and explain first...
 
 // Predict the output of the following code:
-// =============> Write your prediction here
+// =============> Since 'num' is defined as a global variable,
+// the function getLastDigit will always return the last digit of 103.
 
 const num = 103;
 
@@ -14,11 +15,21 @@ 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
+// =============> 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 output is always 3 because the variable `num` is defined globally as 103,
+// and the function `getLastDigit` is not using any parameter.
+
 // Finally, correct the code to fix the problem
-// =============> write your new code here
+// =============> Here's the corrected code:
+function getLastDigit(num) {
+  return num.toString().slice(-1);
+}
 
-// This program should tell the user the last digit of each number.
-// Explain why getLastDigit is not working properly - correct the problem
+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-2/3-mandatory-implement/1-bmi.js

@@ -15,5 +15,13 @@
 // 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
-}
+  const bmi = weight / (height * height);
+  return bmi.toFixed(1);
+}
+
+console.log(
+  `The BMI for a person weighing 100kg and 1.85m tall is ${calculateBMI(
+    70,
+    1.73
+  )}`
+); // Expected output: 23.4

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

@@ -14,3 +14,9 @@
 // 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 upperSnakeCase(str) {
+  let stringInput = `${str.replace(/ /g, "_")}`;
+  let stringInput_final = stringInput.toUpperCase();
+  return stringInput_final;
+}

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(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");
+
+  const finalResult = `£${pounds}.${pence}`;
+
+  return finalResult;
+}
+
+console.log(toPounds("399p"));

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

@@ -17,18 +17,20 @@ function formatTimeDisplay(seconds) {
 // Questions
 
 // a) When formatTimeDisplay is called how many times will pad be called?
-// =============> write your answer here
+// =============> 'pad' will be called 3 times when 'formatTimeDisplay' is called.
 
 // 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 in this case will be 0.
 
-// c) What is the return value of pad is called for the first time?
-// =============> write your answer here
+// c) What is the return value of pad when it's called for the first time?
+// =============> 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 when pad is called for the last time,
+//  it is called with the 'remainingSeconds', which is 1 in this case.
 
 // 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' is still 1 for the reasons cited above.
+// The return value of pad might be different in this case, but it's not asked.