London | 26-ITP-Jan | Abdul Moiz | Sprint 1 | Sprint-1

Sprint-1/1-key-exercises/1-count.js

@@ -4,3 +4,5 @@ count = count + 1;
 
 // Line 1 is a variable declaration, creating the count variable with an initial value of 0
 // Describe what line 3 is doing, in particular focus on what = is doing
+
+// Line 3 is updating the value of the count variable by adding 1 to its current value

Sprint-1/1-key-exercises/2-initials.js

@@ -5,7 +5,6 @@ let lastName = "Johnson";
 // Declare a variable called initials that stores the first character of each string.
 // This should produce the string "CKJ", but you must not write the characters C, K, or J in the code of your solution.
 
-let initials = ``;
+let initials = firstName.charAt(0) + middleName.charAt(0) + lastName.charAt(0);
 
 // https://www.google.com/search?q=get+first+character+of+string+mdn
-

Sprint-1/1-key-exercises/3-paths.js

@@ -17,7 +17,7 @@ console.log(`The base part of ${filePath} is ${base}`);
 // Create a variable to store the dir part of the filePath variable
 // Create a variable to store the ext part of the variable
 
-const dir = ;
-const ext = ;
+const dir = filePath.slice(0, lastSlashIndex);
+const ext = base.slice(base.lastIndexOf("."));
 
-// https://www.google.com/search?q=slice+mdn
+// https://www.google.com/search?q=slice+mdn

Sprint-1/1-key-exercises/4-random.js

@@ -7,3 +7,10 @@ const num = Math.floor(Math.random() * (maximum - minimum + 1)) + minimum;
 // Try breaking down the expression and using documentation to explain what it means
 // It will help to think about the order in which expressions are evaluated
 // Try logging the value of num and running the program several times to build an idea of what the program is doing
+
+// Math.random() generates a random decimal number between 0 and 1.
+// Since the minimum is 1 and maximum is 100 the bracket (maximum - minimum + 1) will always equal 100.
+// The random decimal number is then multiplied by 100, resulting in a random decimal number between 0 and 100.
+// Math.floor() then rounds this decimal number down to the nearest whole number.
+// Finally, the minimum value (1) is added
+// Resulting in a final value of num being a random whole number between 1 and 100.

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

@@ -1,2 +1,4 @@
-This is just an instruction for the first activity - but it is just for human consumption
-We don't want the computer to run these 2 lines - how can we solve this problem?
+//This is just an instruction for the first activity - but it is just for human consumption
+//We don't want the computer to run these 2 lines - how can we solve this problem?
+
+// Commenting out the lines above will prevent the computer from running them

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

@@ -1,4 +1,8 @@
 // trying to create an age variable and then reassign the value by 1
 
-const age = 33;
+let age = 33;
 age = age + 1;
+
+console.log(age);
+
+// Changed const to let to allow reassignment because const variables cannot be reassigned

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

@@ -1,5 +1,8 @@
 // Currently trying to print the string "I was born in Bolton" but it isn't working...
 // what's the error ?
 
-console.log(`I was born in ${cityOfBirth}`);
 const cityOfBirth = "Bolton";
+console.log(`I was born in ${cityOfBirth}`);
+
+// The variable was being called before it was declared. Moved the declaration of
+// the variable to the top to fix the error.

Sprint-1/2-mandatory-errors/3.js

@@ -1,9 +1,13 @@
 const cardNumber = 4533787178994213;
-const last4Digits = cardNumber.slice(-4);
+//const last4Digits = cardNumber.slice(-4);
 
 // The last4Digits variable should store the last 4 digits of cardNumber
 // However, the code isn't working
 // Before running the code, make and explain a prediction about why the code won't work
 // Then run the code and see what error it gives.
 // Consider: Why does it give this error? Is this what I predicted? If not, what's different?
 // Then try updating the expression last4Digits is assigned to, in order to get the correct value
+
+// Error is because cardNumber is a number and numbers don't have the slice method.
+const last4Digits = cardNumber.toString().slice(-4);
+console.log(last4Digits);

Sprint-1/2-mandatory-errors/4.js

@@ -1,2 +1,9 @@
-const 12HourClockTime = "20:53";
-const 24hourClockTime = "08:53";
+// const 12HourClockTime = "20:53";
+// const 24hourClockTime = "08:53";
+
+// Error is because variable names cannot start with a number.
+
+const hour12ClockTime = "20:53";
+const hour24ClockTime = "08:53";
+console.log(hour12ClockTime);
+console.log(hour24ClockTime);

Sprint-1/3-mandatory-interpret/1-percentage-change.js

@@ -2,7 +2,7 @@ let carPrice = "10,000";
 let priceAfterOneYear = "8,543";
 
 carPrice = Number(carPrice.replaceAll(",", ""));
-priceAfterOneYear = Number(priceAfterOneYear.replaceAll("," ""));
+priceAfterOneYear = Number(priceAfterOneYear.replaceAll(",", ""));
 
 const priceDifference = carPrice - priceAfterOneYear;
 const percentageChange = (priceDifference / carPrice) * 100;
@@ -12,11 +12,19 @@ console.log(`The percentage change is ${percentageChange}`);
 // Read the code and then answer the questions below
 
 // a) How many function calls are there in this file? Write down all the lines where a function call is made
+// 5 functions calls. They are on lines, 4, 5, and 10
 
 // b) Run the code and identify the line where the error is coming from - why is this error occurring? How can you fix this problem?
+// There was a comma missing in line 5 in replaceAll("," ""). This was needed because replaceAll is a
+// function that takes two arguments. The missing comma caused a syntax error.
 
 // c) Identify all the lines that are variable reassignment statements
+// Lines 4 and 5 are variable reassignment statements where carPrice and priceAfterOneYear are
+// reassigned new values.
 
 // d) Identify all the lines that are variable declarations
+// Lines 1, 2, 7 and 8 are variable declarations where carPrice and priceAfterOneYear are declared.
 
 // e) Describe what the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression?
+// Number(carPrice.replaceAll(",", "")) removes all commas from the string carPrice and then converts it to a
+// number.

Sprint-1/3-mandatory-interpret/2-time-format.js

@@ -12,14 +12,21 @@ console.log(result);
 // For the piece of code above, read the code and then answer the following questions
 
 // a) How many variable declarations are there in this program?
+// 6 variable declarations.
 
 // b) How many function calls are there?
+// 1 function call - console.log(result)
 
 // c) Using documentation, explain what the expression movieLength % 60 represents
 // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Arithmetic_Operators
+// The expression returns the remainder left over when movieLength is divided by 60. In this case.
 
 // d) Interpret line 4, what does the expression assigned to totalMinutes mean?
+// The expression on line 4 calculates the length of the movie in minutes.
 
 // e) What do you think the variable result represents? Can you think of a better name for this variable?
+// Result represents the movie length formatted as hours:minutes:seconds. A better name could be
+// formattedMovieLength.
 
 // f) Try experimenting with different values of movieLength. Will this code work for all values of movieLength? Explain your answer
+// As long as movieLength is a non-negative integer representing seconds, the code will work.

Sprint-1/3-mandatory-interpret/3-to-pounds.js

@@ -25,3 +25,8 @@ console.log(`£${pounds}.${pence}`);
 
 // To begin, we can start with
 // 1. const penceString = "399p": initialises a string variable with the value "399p"
+// 3. creates a new string by removing the last character ('p') from penceString
+// 8. ensures the pence amount has at least three digits by adding zeros in front if needed
+// 9. takes the first character of the string which represents the pound
+// 14. takes the last two characters of the string which represent the pence
+// 18. outputs the formatted price in pounds and pence to the console