West-Midlands |26-May-ITP |Maryam Janjua |Sprint 1 |Complete Sprint 1 Course Work

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

@@ -4,3 +4,7 @@ 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
+/*
+In line 3, it firstly execute count + 1 i.e 1 and then new value of count is store into variable count.
+The value of count is initially 0 and then in line three it added by 1 so new value of count becomes 1.
+*/

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

@@ -5,7 +5,8 @@ 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);
+console.log(initials);
 
 // https://www.google.com/search?q=get+first+character+of+string+mdn
 

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

@@ -17,7 +17,15 @@ 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 lastindex1 = filePath.lastIndexOf("/");
+const dir1 = filePath.slice(0,lastindex1);
+console.log(`The variable contains directory path of a file: ${dir1}`); 
+const dir = filePath.slice(0,44);
+console.log(`This variable stores directory path of a file: ${dir}`);
+//I did from both ways just to clear my concepts.
+
+const lastext = filePath.lastIndexOf("/");
+const ext = filePath.slice(lastext+5);
+console.log(`This is extension part of a file: ${ext}`);
 
 // https://www.google.com/search?q=slice+mdn

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

@@ -2,8 +2,16 @@ const minimum = 1;
 const maximum = 100;
 
 const num = Math.floor(Math.random() * (maximum - minimum + 1)) + minimum;
+console.log(num);
 
 // In this exercise, you will need to work out what num represents?
 // 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
+
+/*
+The num is a variable that hold a random variable every time we run the code it gives us a different random number.
+In the above expression, firstly it will solve the parenthesis part i.e maximum - minimum +1.
+i.e, (100 - 1 +1)-> 100 then it will evaluate Math.random, Math.random generate any number from 0-1 and it will multiply by 
+100 and added by minimum value i.e 1. Math.floor makes the value round if it is in decimal.
+*/

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?
+
+//As age was constant there we can't change the value of age like this. I made age let so it can change the value of age.

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

@@ -1,4 +1,9 @@
 // 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);
+
+/*As age was constant here we can't change the value of age like this.
+because in line 4, the value of age is incremented by 1 and assigning again to age but if variable is const we can't change.
+I made age let so I can change the value of age.*/

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

@@ -1,5 +1,13 @@
 // 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}`);
+
+/* 
+It a reference error, we cannot access cityOfBirth before initializing it. We are trying to fetch a 
+value of cityOfbirth without declaring it. The interpreter first runs the line 1 i.e console.log one 
+and try to find a value but its not declare and it will give a error. Though we have declare is in line 2 
+but js is an interpreted language that interpret line by line and runs the code.
+The cityOfBirth is in locked state right now js couldn't access until reaches to it. 
+Right now it is in temporal locked state. 
+*/

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

@@ -1,9 +1,24 @@
-const cardNumber = 4533787178994213;
+const cardNumber = "4533787178994213";
 const last4Digits = cardNumber.slice(-4);
+console.log(last4Digits);
+
+//const cardNumber = 4533787178994213;
+//const lastdig = cardNumber.toString().slice(-4);
+//console.log(lastdig);
 
 // 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
+
+/* 
+Slice is a string method we are using it on number.
+We can convert the number into string and then apply slice() method to retrieve last four digits or simply we 
+can declare number as a string using quotes.
+Run a code : It gives TypeError and js gives this error when method/operation isn't valid for particular data 
+type using.
+I got the idea of data type that slice() method can't use for this data type.
+I attempt it by both ways I mentioned above.
+*/

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

@@ -1,2 +1,6 @@
-const 12HourClockTime = "8:53pm";
-const 24hourClockTime = "20:53";
+const HourClockTime12 = "8:53pm";
+const hourClockTime24 = "20:53";
+
+/*The variable name cannot start with number. It can begin with _, $ or a letter.
+I fixed it by renaming the variable names.
+*/

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 +12,24 @@ 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
+/*
+replaceAl() : In line 4, replaceAll(",", "") and in line 5, replaceAll("," "")
+Number() : In line 4, Number(carPrice.replaceAll(",", "")) and in line 5, Number(priceAfterOneYear.replaceAll("," "")
+console.log:  In line 10, console.log(`The percentage change is ${percentageChange}`);
+ */
 
 // 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?
+//Basically, the error is coming from line 5. It missed the , between two values. 
+//priceAfterOneYear = Number(priceAfterOneYear.replaceAll("," , ""));
 
 // c) Identify all the lines that are variable reassignment statements
+//line 4 and line 5
 
 // d) Identify all the lines that are variable declarations
+//line 1, line 2, line 7 and line 8
 
 // e) Describe what the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression?
+/* Number(carPrice.replaceAll(",","")) let's breakdown this to understand.
+carPrice.replaceAll(",","") -> replaces , and it becomes 1000
+Number("1000") converts string to a number -> 1000.
+*/

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

@@ -1,5 +1,5 @@
-const movieLength = 8784; // length of movie in seconds
-
+//const movieLength = 8784; // length of movie in seconds
+const movieLength = 9893; 
 const remainingSeconds = movieLength % 60;
 const totalMinutes = (movieLength - remainingSeconds) / 60;
 
@@ -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?
+//six
 
 // b) How many function calls are there?
+// 1 i.e console.log
 
 // c) Using documentation, explain what the expression movieLength % 60 represents
 // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Arithmetic_Operators
+// This is a reminder operator. It divides one number by another and gives a reminder.
 
 // d) Interpret line 4, what does the expression assigned to totalMinutes mean?
-
+/* const totalMinutes = (movieLength - remainingSeconds) / 60 
+Firstly it will evaluate bracket i.e (movieLength - remainingSeconds) and then divide the value by 60.
+*/
 // e) What do you think the variable result represents? Can you think of a better name for this variable?
-
+// The result represents the how long the movie is, in hours, minutes and seconds. It can named as MovieDuration.
 // f) Try experimenting with different values of movieLength. Will this code work for all values of movieLength? Explain your answer
+// Yes, I changed the value of movieLength and it worked. The movieLength is the variable used in calculating other 
+// values and to evaluate the total length of movie.

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

@@ -25,3 +25,29 @@ console.log(`£${pounds}.${pence}`);
 
 // To begin, we can start with
 // 1. const penceString = "399p": initialises a string variable with the value "399p"
+/*line 3-6. 
+const penceStringWithoutTrailingP = penceString.substring(
+  0,
+  penceString.length - 1
+) : calculate  the length and then subtract 1,length is 4-1=3 , and extract substring 0 to 3 i.e 399
+
+line 8.Padstart puts zero in beginning until it meets the desire length. The length is 3 and string length is already 3, so it remained unchanged.
+paddedPenceNumberString = "399"
+
+line 9-12. 
+const pounds = paddedPenceNumberString.substring(
+  0,
+  paddedPenceNumberString.length - 2
+); paddedPenceNumberString.length - 2: 3-2=1 -> paddedPenceNumberString.substring(0,1)-> pounds="3"
+l
+ine 14-16.
+const pence = paddedPenceNumberString
+  .substring(paddedPenceNumberString.length - 2)
+  .padEnd(2, "0");
+(paddedPenceNumberString.length - 2)-> 3-2 = 1 -> substring(1).padEnd(2,"0")-> 99, the length is already two.
+pence ="99"
+
+line 18.
+console.log(`£${pounds}.${pence}`);
+£3.99
+*/

Sprint-1/4-stretch-explore/chrome.md

@@ -8,11 +8,12 @@ Just like the Node REPL, you can input JavaScript code into the Console tab and
 Let's try an example.
 
 In the Chrome console,
-invoke the function `alert` with an input string of `"Hello world!"`;
+invoke the function `alert` with an input string of `"Hello world!"`; it displays hello world in a alert box
 
-What effect does calling the `alert` function have?
+What effect does calling the `alert` function have? the alert function forces browser to display a message or a warning.
 
 Now try invoking the function `prompt` with a string input of `"What is your name?"` - store the return value of your call to `prompt` in an variable called `myName`.
-
-What effect does calling the `prompt` function have?
-What is the return value of `prompt`?
+Prompt("what is your name?"), it pops-up a dialog box where I enter my name.
+I saved my name in a variable myName and I called the prompt function, it gives my name.
+What effect does calling the `prompt` function have? by prompt you can write/give your input or user can cancel it
+What is the return value of `prompt`? name user have input or null in case of cancel.

Sprint-1/4-stretch-explore/objects.md

@@ -4,13 +4,17 @@ In this activity, we'll explore some additional concepts that you'll encounter i
 
 Open the Chrome devtools Console, type in `console.log` and then hit enter
 
-What output do you get?
+What output do you get? -> it says there a function log inside console.
 
-Now enter just `console` in the Console, what output do you get back?
+Now enter just `console` in the Console, what output do you get back? it says there a function log inside console.
 
-Try also entering `typeof console`
+Try also entering `typeof console` ->object, console is a built-in object.
 
 Answer the following questions:
 
 What does `console` store?
+It doesn't store anything, It is a debugging object that enables you to interact with browser's developers tools.
 What does the syntax `console.log` or `console.assert` mean? In particular, what does the `.` mean?
+console.log -> it prints normal messages
+console.assert -> it is conditional debugger, it checks the condition. If its true it gives nothing and if its false it displays message in console.
+The dot . it means to access inside the object.