Glasgow | 25-ITP-SEP | Shreef Ibrahim | Sprint 1 | Coursework

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
+// is assignment it takes the variable vlue, which is 0 and add 1.
+// // Since count was initially 0, this becomes: count = 0 + 1, so count now holds the value 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) ==> CKJ
 
 // https://www.google.com/search?q=get+first+character+of+string+mdn
 

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

@@ -14,10 +14,13 @@ const lastSlashIndex = filePath.lastIndexOf("/");
 const base = filePath.slice(lastSlashIndex + 1);
 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 lastDoutIndex = base.lastIndexOf(".")
+const ext = base.slice(lastDoutIndex)
 
 // https://www.google.com/search?q=slice+mdn

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

@@ -7,3 +7,11 @@ 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
+console.log(num)
+//num is a random number between the minimum and  maximum.
+// 1. Math.random() static method returns a floating-point, pseudo-random number that's greater than or equal to 0 and less than 1
+// 2. (maximum - minimum + 1) Calculates the range of values, including both ends.
+    // For 1 to 100, this is:
+    // 100 - 1 + 1 = 100
+    //3- Math.floor() static method always rounds down and returns the largest integer less than or equal to a given number.
+      // example Math.floor(50.9) = 50  

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?
+// we could add a Single-line comment // .or  Multi-line comment /* */
+// Now JavaScript will ignore those lines, and they will not affect our program.

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

@@ -1,4 +1,6 @@
 // trying to create an age variable and then reassign the value by 1
 
-const age = 33;
+// const age = 33;
+let age = 33;
 age = age + 1;
+

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

@@ -1,5 +1,7 @@
 // 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}`);
+// console.log(`I was born in ${cityOfBirth}`);
 const cityOfBirth = "Bolton";
+console.log(`I was born in ${cityOfBirth}`);
+// Variables declared with (const) (or let) are not accessible before their declaration, even though they are hoisted (set aside in memory).
+// // So, when console.log(...) runs, cityOfBirth exists in memory but is not yet initialized, so trying to access it throws an error.

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

@@ -1,9 +1,12 @@
-const cardNumber = 4533787178994213;
-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
+// .slice() called on a number, and  Numbers don’t have string methods like .slice().it will throw an error
+// console.log(last4Digits) => TypeError: cardNumber.slice is not a function at Object.
+const cardNumber = 4533787178994213;
+// const last4Digits = cardNumber.toString;
+const last4Digits = cardNumber % 10000;
+console.log(last4Digits)

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

@@ -1,2 +1,7 @@
-const 12HourClockTime = "20:53";
-const 24hourClockTime = "08:53";
+// const 12HourClockTime = "20:53";
+// const 24hourClockTime = "08:53";
+// JavaScript does not allow variable names to begin with a digit. The variable name 12HourClockTime starts with 12,
+//  which is not valid syntax, and will throw a SyntaxError:
+
+const hourClockTime24 = "20:53";
+const hourClockTime12 = "08:53";

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 +12,21 @@ 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 in 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?
+//        SyntaxError: missing ) after argument list is  Missing comma between arguments
 
 // c) Identify all the lines that are variable reassignment statements
+//         Line 4 :carPrice = Number(carPrice.replaceAll(",", ""));
+//        Line 5:priceAfterOneYear = Number(priceAfterOneYear.replaceAll("," ""));
 
 // d) Identify all the lines that are variable declarations
+//        Line 1: let carPrice = "10,000";
+//        Line 2: let priceAfterOneYear = "8,543";
+//        Line 7: const priceDifference = carPrice - priceAfterOneYear;
+//        Line 8: const percentageChange = (priceDifference / carPrice) * 100;
 
 // e) Describe what the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression?
+//    removes all commas from the string "10,000", making it "10000". and Number(...): converts the resulting string "10000" to a number type 10000.
+//    so the purpose is to  convert a comma-formatted string into a usable numeric value for mathematical operation.

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

@@ -11,15 +11,24 @@ 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?
+// a) How many variable declarations are there in this program
+//     6 variable declared
 
 // b) How many function calls are there?
+//   1 function in line 10
 
 // c) Using documentation, explain what the expression movieLength % 60 represents
+//The remainder (%) operator returns the remainder
+// so is divide movieLength by 60 and return the remainder."
 // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Arithmetic_Operators
 
 // d) Interpret line 4, what does the expression assigned to totalMinutes mean?
+//First, it takes away the extra seconds that don't make up a full minute.
+// Then it divides the remaining seconds by 60 to figure out how many complete minutes are in the movie.
 
 // e) What do you think the variable result represents? Can you think of a better name for this variable?
+// formattedTime
 
 // f) Try experimenting with different values of movieLength. Will this code work for all values of movieLength? Explain your answer
+// Yes  but not all  ,because It handles converting seconds into minutes and hours using integer division and modulus.But with negative  integers dose not work correcly
+//And does not pad single-digit values with zeroes as wll, It will return something like 2:4:7 instead of 02:04:07, which is not a standard time format.

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

@@ -25,3 +25,24 @@ console.log(`£${pounds}.${pence}`);
 
 // To begin, we can start with
 // 1. const penceString = "399p": initialises a string variable with the value "399p"
+// Initializes a string that represents an amount in (pence), ending with a `"p"` to signify pence (e.g., `"399p"` = 399 pence).
+
+//2- const penceStringWithoutTrailingP = penceString.substring(0,penceString.length - 1);
+// this Removes the trailing "p" from the string.so it is substring(0, penceString.length - 1)
+// takes all characters except the last. for example For "399p", this returns "399".
+
+// 3-const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0");
+// Pads the number with leading zeros to ensure it is at least 3 digits long. so it helps normalise values like "5" → "005" and "99" → "099".
+
+// 4  const pounds = paddedPenceNumberString.substring(0, paddedPenceNumberString.length - 2);
+//  Extracts the pounds from the padded string.so it takes all digits except the last two.
+//For "399", this gives "3" → meaning 3 pounds.
+
+//5- const pence = paddedPenceNumberString.substring(paddedPenceNumberString.length - 2).padEnd(2, "0");
+// Extracts the last two digits for pence and pads them if necessary.
+// substring(length - 2) takes the final 2 characters.
+// padEnd(2, "0") ensures the pence string is exactly 2 digits. transfer to two-digit formatting for pence 5 => "05".
+
+//6-  console.log(`£${pounds}.${pence}`);
+//this log the final formatted string in pounds and pence using a template literal.
+// For "399p", output is: £3.99