Glasgow | 25-ITP-SEP | Hanna Mykytiuk | Sprint 1 | coursework/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
+//Answer:
+//In line 3 to existing variable count assigned new value = old value of variable + 1.

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

@@ -5,7 +5,9 @@ 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)}+${lastName.charAt(0)}}`;
+    let initials = `${firstName.charAt(0)+middleName.charAt(0)+lastName.charAt(0)}`;
+    console.log(`The initials are: ${initials}`)
 
 // https://www.google.com/search?q=get+first+character+of+string+mdn
 

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

@@ -11,13 +11,17 @@
 
 const filePath = "/Users/mitch/cyf/Module-JS1/week-1/interpret/file.txt";
 const lastSlashIndex = filePath.lastIndexOf("/");
+console.log(`Last slash index ${lastSlashIndex}`)
 const base = filePath.slice(lastSlashIndex + 1);
+console.log(`Base: ${base}`)
 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 + 1);
+console.log(`The dir part is: ${dir}`);
+const ext = console.log(`The ext part is: ${filePath.slice(-3)}`) ;
 
 // 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
+console.log(num)
+
+//Explenation:
+
+// Math.random - generates a random number (could be anything like: 0,1-0,750 etc in the range from 0(inclusive) to 1 (exclusive));
+// Math.floar - rounds the number to the closest integer;
+// Consequently, given expression on line 4 gives us a random round number in the range from minimum to maximum.

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?
+We don't want the computer to run these 2 lines - how can we solve this problem?
+
+//We have to add " // "

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

@@ -2,3 +2,5 @@
 
 const age = 33;
 age = age + 1;
+
+// declared variable is const which means that can't be changed (Should be assigned like "let age");

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

@@ -3,3 +3,5 @@
 
 console.log(`I was born in ${cityOfBirth}`);
 const cityOfBirth = "Bolton";
+
+//The variable declaration should be on the beginning

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

@@ -7,3 +7,8 @@ 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
+
+
+//Explenation: method Slice is valid for String type.
+//we need to change a type:
+//const last4Digits = cardNumber.toString.slice(-4);

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

@@ -1,2 +1,4 @@
 const 12HourClockTime = "20:53";
-const 24hourClockTime = "08:53";
+const 24hourClockTime = "08:53";
+
+//Explenation: the name of value in  JS can not start with numbers.

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 +12,13 @@ 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
-
+    //4,5
 // 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?
-
+    //
 // c) Identify all the lines that are variable reassignment statements
-
+    //4,5
 // d) Identify all the lines that are variable declarations
-
+    //1,2,7,8
 // e) Describe what the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression?
+    // we replace all commas into "". Then, we convert variable CarPrice into Integer, because it was String. 
+    // The purpose of this action is next step of calculation.

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

@@ -1,6 +1,7 @@
-const movieLength = 8784; // length of movie in seconds
+const movieLength = -8784; // length of movie in seconds (8784)
 
 const remainingSeconds = movieLength % 60;
+//console.log(`Remaining Seconds:${remainingSeconds}`)
 const totalMinutes = (movieLength - remainingSeconds) / 60;
 
 const remainingMinutes = totalMinutes % 60;
@@ -12,14 +13,16 @@ 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
 // b) How many function calls are there?
-
+        //1
 // 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 remaider operator that help us get remaining. In this case, dividing MovieLength % 60 returned 
+        // remainder. It is not a typical mathematic division, it is division where we can get remainder.
 // d) Interpret line 4, what does the expression assigned to totalMinutes mean?
-
+        // Mean the subtraction remaider(second)  from the total length (in second) and divide by 60, because we need Minutes (1 min = 60 sec)
 // e) What do you think the variable result represents? Can you think of a better name for this variable?
-
+        //time
 // f) Try experimenting with different values of movieLength. Will this code work for all values of movieLength? Explain your answer
+        //It works with a different values(negative and positive numbers).

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

@@ -1,19 +1,15 @@
 const penceString = "399p";
 
-const penceStringWithoutTrailingP = penceString.substring(
-  0,
-  penceString.length - 1
-);
+const penceStringWithoutTrailingP = penceString.substring( 0,penceString.length - 1);
+console.log(penceStringWithoutTrailingP);
 
 const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0");
-const pounds = paddedPenceNumberString.substring(
-  0,
-  paddedPenceNumberString.length - 2
-);
+console.log(paddedPenceNumberString);
+const pounds = paddedPenceNumberString.substring(0, paddedPenceNumberString.length - 2);
+console.log(pounds);
 
-const pence = paddedPenceNumberString
-  .substring(paddedPenceNumberString.length - 2)
-  .padEnd(2, "0");
+const pence = paddedPenceNumberString.substring(paddedPenceNumberString.length - 2).padEnd(2, "0");
+console.log(pence); 
 
 console.log(`£${pounds}.${pence}`);
 
@@ -25,3 +21,8 @@ console.log(`£${pounds}.${pence}`);
 
 // To begin, we can start with
 // 1. const penceString = "399p": initialises a string variable with the value "399p"
+// 3. declaration of penceStringWithoutTrailingP, that = 399 because of method substracting()
+// 6. declaration of paddedPenceNumberString, that = 399 because of padStart(3, "0")
+// 8. declaration of paddedPenceNumberString, substring() cut two last characters, padEnd(3,"0") - add "0" on the right side.
+// 11. declaration of pence, that substring(two last characters of paddedPenceNumberString ) and padEnd(2, "0") that may add two "00" in the end of the right side.
+// 14. shoows pounds and pence with special sign and comma.

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

@@ -11,8 +11,10 @@ In the Chrome console,
 invoke the function `alert` with an input string of `"Hello world!"`;
 
 What effect does calling the `alert` function have?
-
+    //pop up window appeared.
 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?
+     //pop up with input appeared
 What is the return value of `prompt`?
+    //return value is user input

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

@@ -4,13 +4,18 @@ 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? 
+
+//ƒ log() { [native code] }
 
 Now enter just `console` in the Console, what output do you get back?
+// console {debug: ƒ, error: ƒ, info: ƒ, log: ƒ, warn: ƒ, …}
 
 Try also entering `typeof console`
-
+// 'object'
 Answer the following questions:
 
 What does `console` store?
+// Console is JS object for logging output. 
 What does the syntax `console.log` or `console.assert` mean? In particular, what does the `.` mean?
+// log() and assert() are method of console object that can be accesed with "." notation.