Completed Sprint-2

Author: KKtech06

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

@@ -1,5 +1,7 @@
 // Predict and explain first...
 //  =============> write your prediction here
+// This function is trying to capitalise the first letter of a string.
+// it takes the first character using str[0], converts it to uppercase,and joins it with the rest of the string using str.slice(1).
 
 // call the function capitalise with a string input
 // interpret the error message and figure out why an error is occurring
@@ -10,4 +12,9 @@ function capitalise(str) {
 }
 
 // =============> write your explanation here
-// =============> write your new code here
+// The error is occurring because the function is trying to declare a variable with the same name as the parameter, which is not allowed in JavaScript.
+// The variable `str` is being redeclared inside the function, causing a syntax error.
+function capitalise(str) {
+  let result = str[0].toUpperCase() + str.slice(1);
+  return result;
+}

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

@@ -2,6 +2,9 @@
 
 // Why will an error occur when this program runs?
 // =============> write your prediction here
+// I predict this function is trying to convert a decimal number
+// into a percentage. It multiples the decimal number by 100 and
+// then it adds the %  symbol to the end of the number.
 
 // Try playing computer with the example to work out what is going on
 
@@ -15,6 +18,18 @@ function convertToPercentage(decimalNumber) {
 console.log(decimalNumber);
 
 // =============> write your explanation here
+// The error happens becouse 'decimalNumber' is already the parameter
+// of the function. Inside the function the code tries to declare 'decimalNumber'
+// again using the const, which is not allowed.
+
+// a other problem is that console.log(decimalNumber) is outside
+// the function but 'decimalNumber' only exists inside the function.
 
 // 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 +4,27 @@
 // this function should square any number but instead we're going to get an error
 
 // =============> write your prediction of the error here
+// I predict an error will happen becouse the function uses 3 as the parameter
+// but parameters should be varible names. Also the code uses "num" inside the
+// function even though it was never defiend.
 
 function square(3) {
     return num * num;
 }
 
 // =============> write the error message here
+// SyntaxError: Unexpected number
 
 // =============> explain this error message here
+// The error happens becouse 3 is used  as the function parameter  but parameters
+// must be varible names. Also the code tries to use "num" inside the function even
+// though it was never dec;ared.
 
 // 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 +1,9 @@
 // Predict and explain first...
 
 // =============> write your prediction here
+// I predict the program will print 320 first.
+// Then it will print "the result of multipying 10 and 32 is undefined"
+// becouse the function logs the result but does not return it.
 
 function multiply(a, b) {
   console.log(a * b);
@@ -9,6 +12,14 @@ function multiply(a, b) {
 console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);
 
 // =============> write your explanation here
+// The problem is that the function uses console.log insted ofreturning the value.
+// Becouse the function does not return anything, the value of multiply(10, 32)
+// becomes undefined when it is used insdie the temple string.
 
 // 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 +1,8 @@
 // Predict and explain first...
 //  =============> write your prediction here
+// I predict the program will print "The sum of 10 and 32 is underfined"
+// becouse the return statment does not return a value and the addition
+// is written on the next line.
 
 function sum(a, b) {
   return;
@@ -9,5 +12,12 @@ function sum(a, b) {
 console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);
 
 // =============> write your explanation here
+// The problem is that the return us written on its own line.
+// Becouse of this, the function returns undefined before executing a + 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-2/2-mandatory-debug/2.js

@@ -2,6 +2,11 @@
 
 // Predict the output of the following code:
 // =============> Write your prediction here
+// I predict the program will print:
+// The last digit of 42 is 3
+// The last digit of 105 is 3
+// The last digit of 806 is 3
+// This happens because the function always uses the variable num which is 103.
 
 const num = 103;
 
@@ -15,10 +20,25 @@ 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 problem is that the function always uses the varible num which is 103.
+// Becouse of this, the last digit is always 3.
+// The numbers passed into the function (42, 105, 806) are ignored.
+
 // 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

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

@@ -15,5 +15,8 @@
 // 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(calculateBMI(70, 1.73));
+// return the BMI of someone based off their weight and height

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

@@ -14,3 +14,8 @@
 // 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 str.replaceAll(" ", "_").toUpperCase();
+}
+console.log(toUpperSnakeCase("hello there"));

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

@@ -4,3 +4,10 @@
 // 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(pence) {
+    return "£" + (pence / 100).toFixed(2);
+}
+console.log(toPounds(399));
+console.log(toPounds(250));
+console.log(toPounds(100));

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

@@ -18,17 +18,22 @@ function formatTimeDisplay(seconds) {
 
 // a) When formatTimeDisplay is called how many times will pad be called?
 // =============> write your answer here
+// It will be called 3 times becouse it is used three times in the return line.
 
 // 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 is 0 becouse totalHours is 0 when the input is 61 seconds.
 
 // c) What is the return value of pad is called for the first time?
 // =============> write your answer here
+// The return value is "00" beccouse padStart adds a 0 in front to make it two 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 is 1 becouse remainingSeconds is 1 when the input is 61 seconds.
 
 // 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" becouse padStart adds a 0 at the beginning ti make it two digits.