Manchester | 26-ITP-May | Monsur Abdulrahman | Sprint 2 | implement and rewrite tests

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

@@ -1,8 +1,18 @@
 // Predict and explain first...
 //  =============> write your prediction here
+//There will be a syntax error when the function   `capitalise` is called 
+//because the variable `str` is being declared twice in the same scope. 
+//The first declaration is in the function parameter, and the second declaration 
+//is inside the function body. This will cause a "SyntaxError: Identifier 'str' has 
+//already been declared" error.
+
+
 
-// call the function capitalise with a string input
 // interpret the error message and figure out why an error is occurring
+//The error occurs because the variable `str` is being declared twice in the same 
+//scope. The first declaration is in the function parameter, and the second 
+//declaration is inside the function body. This causes a "SyntaxError: Identifier 'str' 
+//has already been declared" error.
 
 function capitalise(str) {
   let str = `${str[0].toUpperCase()}${str.slice(1)}`;
@@ -11,3 +21,7 @@ function capitalise(str) {
 
 // =============> write your explanation here
 // =============> write your new code here
+function capitalise(str) {
+  let capitalisedStr = `${str[0].toUpperCase()}${str.slice(1)}`;
+  return capitalisedStr;
+}

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

@@ -2,6 +2,8 @@
 
 // Why will an error occur when this program runs?
 // =============> write your prediction here
+The error will occur because the variable `decimalNumber` is being declared twice in 
+the same scope.
 
 // Try playing computer with the example to work out what is going on
 
@@ -16,5 +18,18 @@ console.log(decimalNumber);
 
 // =============> write your explanation here
 
+An error will occur because the variable `decimalNumber` is being declared twice 
+in the same scope. The first declaration is in the function parameter, 
+and the second declaration is inside the function body. This will cause a 
+"SyntaxError: Identifier 'decimalNumber' has already been declared" error.
+
+
 // 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 +4,25 @@
 // this function should square any number but instead we're going to get an error
 
 // =============> write your prediction of the error here
+//There will be a syntax error.
 
 function square(3) {
     return num * num;
 }
 
 // =============> write the error message here
+// "SyntaxError: Unexpected number"
 
 // =============> explain this error message here
+// The error occurs because the function parameter is defined as a number (3) 
+// instead of a variable name. In JavaScript, function parameters must be variable 
+// names, not values.
 
 // Finally, correct the code to fix the problem
 
 // =============> write your new code here
+function square(num) {
+    return num * num;
+}
 
 

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

@@ -1,6 +1,7 @@
 // Predict and explain first...
 
 // =============> write your prediction here
+// The output of the code will be: undefined.
 
 function multiply(a, b) {
   console.log(a * b);
@@ -9,6 +10,16 @@ function multiply(a, b) {
 console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);
 
 // =============> write your explanation here
+// The function multiply takes two arguments, a and b, and logs their product to 
+// the console. However, it does not return any value, which means that when we 
+// call multiply(10, 32) inside the template literal, it will return undefined. 
+// Therefore, the output of the console.log statement 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

@@ -1,5 +1,6 @@
 // Predict and explain first...
 //  =============> write your prediction here
+// The output of the code will be: undefined.
 
 function sum(a, b) {
   return;
@@ -9,5 +10,14 @@ function sum(a, b) {
 console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);
 
 // =============> write your explanation here
+// The function sum takes two arguments, a and b, and has a return statement that
+// does not return any value. The line a + b is never executed because it comes after
+// the return statement. Therefore, when we call sum(10, 32) inside the template literal,
+// it will return undefined. As a result, the output of the console.log statement will be:
+// "The sum of 10 and 32 is undefined".
+
 // Finally, correct the code to fix the problem
 //  =============> write your new code here
+function sum(a, b) {
+  return a + b;
+}

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

@@ -2,6 +2,8 @@
 
 // Predict the output of the following code:
 // =============> Write your prediction here
+//The output of the code will be: "The last digit of 42 is 3",
+//"The last digit of 105 is 3", "The last digit of 806 is 3".
 
 const num = 103;
 
@@ -15,10 +17,31 @@ 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 of the code is: "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 is not working properly because it does not take any 
+// parameters.
+
 // 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
+//getLastDigit is not working properly because it does not take any parameters. 
+//It always returns the last digit of the number 103, which is hardcoded in the 
+//function. To fix this, we need to modify the function to accept a parameter (num) 
+//and return the last digit of that parameter instead.
+
+
+

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

@@ -16,4 +16,6 @@
 
 function calculateBMI(weight, height) {
     // return the BMI of someone based off their weight and height
+    const bmi = weight / Math.pow(height, 2);
+    return Math.round(bmi * 10) / 10;
 }

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

@@ -11,6 +11,12 @@
 
 // Another example: "lord of the rings" should be "LORD_OF_THE_RINGS"
 
+
 // 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) {
+    // return the string in UPPER_SNAKE_CASE
+    return str.toUpperCase().replace(/ /g, '_');
+}       

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

@@ -4,3 +4,47 @@
 // 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
+
+//(Code copied from Sprint-1 interpret/to-pounds.js)
+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");
+
+console.log(`£${pounds}.${pence}`);
+
+//(Turning it into a resuable block of code)
+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("100p"));
+console.log(toPounds("50p"));

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

@@ -22,17 +22,29 @@ function formatTimeDisplay(seconds) {
 
 // a) When formatTimeDisplay is called how many times will pad be called?
 // =============> write your answer here
+//The function pad will be called 3 times when formatTimeDisplay is called, 
+//once for totalHours, once for remainingMinutes, and once for remainingSeconds.
 
 // 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 when pad is called for the first time is 0, 
+//because 61 seconds is equal to 1 minute and 1 second, which means totalHours 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 it is called for the first time is "00",
+//because the value of num is 0, and the function pad adds a leading zero to 
+// make it a two-digit string.
 
 // 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 in this program is 1,
+//because 61 seconds is equal to 1 minute and 1 second, which means remainingSeconds is 1.
 
 // 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 return value of pad when it is called for the last time in this program is "01",
+//because the value of num is 1, and the function pad adds a leading zero to 
+// make it a two-digit string.