complete sprint 2 exercises

Author: Vaidah-dev

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

@@ -1,6 +1,7 @@
-let count = 0;
-
-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
+let count = 0;
+
+count = count + 1;
+//Line 1 is variable declaration, creating the count variable with an initial value of 0
+//Line 3 takes the current value of count (0), adds 1 to it (0 + 1 = 1), and uses the assignment operator (=) to reassign and store this new value (1) back into the count variable.
+// 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

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

@@ -1,10 +1,12 @@
-const firstName = "Creola";
-const middleName = "Katherine";
-const 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.
-
-const initials = ``;
-
-// https://www.google.com/search?q=get+first+character+of+string+mdn
+const firstName = "Creola";
+const middleName = "Katherine";
+const 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.
+
+const initials = firstName[0] + middleName[0] + lastName[0];
+
+console.log(initials);
+
+// https://www.google.com/search?q=get+first+character+of+string+mdn

Sprint-2/1-key-exercises/3-paths.js

@@ -1,23 +1,26 @@
-// The diagram below shows the different names for parts of a file path on a Unix operating system
-
-// ┌─────────────────────┬────────────┐
-// │          dir        │    base    │
-// ├──────┬              ├──────┬─────┤
-// │ root │              │ name │ ext │
-// "  /    home/user/dir / file  .txt "
-// └──────┴──────────────┴──────┴─────┘
-
-// (All spaces in the "" line should be ignored. They are purely for formatting.)
-
-const filePath = "/Users/mitch/cyf/Module-JS1/week-1/interpret/file.txt";
-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 = ;
-
+// The diagram below shows the different names for parts of a file path on a Unix operating system
+
+// ┌─────────────────────┬────────────┐
+// │          dir        │    base    │
+// ├──────┬              ├──────┬─────┤
+// │ root │              │ name │ ext │
+// "  /    home/user/dir / file  .txt "
+// └──────┴──────────────┴──────┴─────┘
+
+// (All spaces in the "" line should be ignored. They are purely for formatting.)
+
+const filePath = "/Users/mitch/cyf/Module-JS1/week-1/interpret/file.txt";
+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 = filePath.slice(0, lastSlashIndex);
+const ext = filePath.slice(filePath.lastIndexOf("."));
+
+console.log(dir);
+console.log(ext);
+
 // https://www.google.com/search?q=slice+mdn

Sprint-2/1-key-exercises/4-random.js

@@ -1,9 +1,14 @@
-const minimum = 1;
-const maximum = 100;
-
-const num = Math.floor(Math.random() * (maximum - minimum + 1)) + minimum;
-
-// 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
+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
+// Breakdown of the expression
+// 1. Math.random() this generates a decimal number from 0 up to , but not including 1
+//num represents a random number between minimum and maximum

Sprint-2/2-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?
+
+   //answer: by adding the 2 forward slashes before every line

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

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

Sprint-2/2-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";
+// Currently trying to print the string "I was born in Bolton" but it isn't working...
+// what's the error ?
+
+const cityOfBirth = "Bolton";
+console.log(`I was born in ${cityOfBirth}`);
+
+//reason is the console.log was entered before the text
+

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

@@ -1,9 +1,10 @@
-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
+const cardNumber = "4533787178994213";
+const last4Digits = cardNumber.slice(-4);
+console.log(last4Digits);
+
+// 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

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

@@ -1,2 +1,5 @@
-const 12HourClockTime = "8:53pm";
-const 24hourClockTime = "20:53";
+const twelveHourClockTime = "8:53pm";
+const twentyFourHourClockTime = "20:53";
+
+console.log(twelveHourClockTime);
+console.log(twentyFourHourClockTime);

Sprint-2/3-mandatory-interpret/1-percentage-change.js

@@ -1,22 +1,30 @@
-let carPrice = "10,000";
-let priceAfterOneYear = "8,543";
-
-carPrice = Number(carPrice.replaceAll(",", ""));
-priceAfterOneYear = Number(priceAfterOneYear.replaceAll("," ""));
-
-const priceDifference = carPrice - priceAfterOneYear;
-const percentageChange = (priceDifference / carPrice) * 100;
-
-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
-
-// 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
-
-// d) Identify all the lines that are variable declarations
-
-// e) Describe what the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression?
+let carPrice = "10,000";
+let priceAfterOneYear = "8,543";
+
+carPrice = Number(carPrice.replaceAll(",", ""));
+priceAfterOneYear = Number(priceAfterOneYear.replaceAll("," ""));
+
+const priceDifference = carPrice - priceAfterOneYear;
+const percentageChange = (priceDifference / carPrice) * 100;
+
+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
+     //answer: we have 5 function calls across 3 lines: 
+     //line 4
+     //line 5
+    //line 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?
+    //answer: on line 5, there is an error caused by a missing comma replaceAll("," ""));. Can be fixed by changing it to priceAfterOneYear = Number(priceAfterOneYear.replaceAll(",", ""));
+
+// c) Identify all the lines that are variable reassignment statements
+    //answer: lines 4 and 5
+
+// d) Identify all the lines that are variable declarations
+    //answer: line 1, 2, 7 and 8
+
+// e) Describe what the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression?
+    //answer: .ReplaceAll(",", "") this will remove every comma from the price string and number will convert that clean string into a numeric value so mathematical calculations can be performed.