Done Sprint 1

Author: Seti-Jemal

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

@@ -2,4 +2,5 @@ let count = 0;
 
 count = count + 1;
 
-// Line 1 makes a variable called count and gives the value 0. Line 3 ads 1 to the value of count. So after line 3, count has the value 1. If we were to run line 3 again, count would have the value 2. If we were to run line 3 again, count would have the value 3. And so on. Each time we run line 3, we add 1 to the value of count.
+// line 1 makes box called count and puts 0 inside it.
+// line 3 adds 1 to count.

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

@@ -17,6 +17,8 @@ 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 lastDotIndex = base.lastIndexOf(".");
+const ext = filePath.slice(lastDotIndex + 1);
 
+// https://www.google.com/search?q=slice+mdn

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

@@ -7,3 +7,6 @@ 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
+
+//num is random whole number between 1 and 100.
+//each time the program runs, it creates a different number in that range.

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

@@ -1,2 +1,6 @@
 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 don't want the computer to run these 2 lines - how can we solve this problem?
+
+
+// We can add // at the start of the lines to turn them into comments.
+// The computer ignores comments, so it will not run them.

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

@@ -2,3 +2,8 @@
 
 const age = 33;
 age = age + 1;
+
+// The error happens because age was declared using const.
+// const variable canot be changed.
+// We trying to change age ,so casue error.
+// It should use let instead.

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

@@ -3,3 +3,8 @@
 
 console.log(`I was born in ${cityOfBirth}`);
 const cityOfBirth = "Bolton";
+
+// The error happens because cityOfBirth is used before it is declared.
+// Const variable cannot be used before declaration.
+// Move the variable delaration before the console.log line.
+

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

@@ -7,3 +7,9 @@ const last4Digits = cardNumber.slice(-4);
 // 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
+
+
+// The code will not work because slice() cannot be used on numbers.
+// Slice() only works on strings or arrays.
+//We need to convert the number to string first 
+const last4Digits = cardNumber.to String().slice(-4);

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

@@ -1,2 +1,8 @@
 const 12HourClockTime = "20:53";
-const 24hourClockTime = "08:53";
+const 24hourClockTime = "08:53";
+
+// Variables names cannot start with a number.
+// Rename the variables so they start with a letter.
+const hour12ClockTime = "20:35";
+const hour24ClockTime = "08:35";
+

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

@@ -4,19 +4,40 @@ let priceAfterOneYear = "8,543";
 carPrice = Number(carPrice.replaceAll(",", ""));
 priceAfterOneYear = Number(priceAfterOneYear.replaceAll("," ""));
 
-const priceDifference = carPrice - priceAfterOneYear;
-const percentageChange = (priceDifference / carPrice) * 100;
+const PriceDifference = carPrice - priceAfterOneYear;
+const PercentageChange = (PriceDifference / carPrice) * 100;
 
-console.log(`The percentage change is ${percentageChange}`);
+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
+// there are 4 function calls in this file.
+carPrice.replaceAll(",", "")
+priceAfterOneYear.replaceAll(",", "")
+Number(carPrice.replaceAll(",", ""))
+Number(priceAfterOneYear.replaceAll(",", ""))
+
 
 // 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?
+// the error is comin from this line 
+
+priceAfterOneYear = Number(priceAfterOneYear.replaceAll("," ""));
+// the error happens becuae there is missing comma inside reaplaceAll().
+//The correct line should be 
+priceAfterOneYear = Number(priceAfterOneYear.replaceAll(",", ""));
 
 // c) Identify all the lines that are variable reassignment statements
+// This lines 
+carPrice = Number(carPrice.reaplaceAll(",", ""));
 
 // d) Identify all the lines that are variable declarations
+let carPrice = 10,000";
+let priceAfterOneYear = "8,543";
+const priceDifference = carPrice - priceAfterOneyear;
+const percentageChange = (priceDifference / carPrice) * 100;
+
 
 // e) Describe what the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression?
+Number(carPrice.replaceAll(",", ""))
+// It removes commas from the number string and converts the results into  a real number so calculation can be done.

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

@@ -12,14 +12,35 @@ 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?
+There are 6 variable declarations in this program.
+    movieLength
+remainingSeconds
+totalMinutes
+remainingMinutes
+totalHours
+result
 
 // b) How many function calls are there?
+There is 1 function call in this program.
+    console.log(result)
+// The function call is on line 10, where we are calling the console.log function to print the value of result to the console.
 
 // c) Using documentation, explain what the expression movieLength % 60 represents
 // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Arithmetic_Operators
 
+// % is the remainder after dividing movielenth by 60. It gives us the number of seconds that are left over after we have taken out all the whole minutes from the movie length
+
+
+
 // d) Interpret line 4, what does the expression assigned to totalMinutes mean?
+// first remove the extra seconds.
+// then divide by 60 to get the total number of minutes in the movie length.
 
 // e) What do you think the variable result represents? Can you think of a better name for this variable?
+// The variable result represents the formatted time in hours:minutes:seconds format.
+// A better name for this varibale could be formattedTime.
 
 // f) Try experimenting with different values of movieLength. Will this code work for all values of movieLength? Explain your answer
+// no, this code will not work good for all values of movielength.
+// it will only right for postitive whole number of seconds.
+// if movieLength is nagatuve or not a whole number, the result will not be right.