DEV Community: Achilonu Chinwendu Faustina

Mastering Conditional Statements, Loops, and FizzBuzz in JavaScript

Achilonu Chinwendu Faustina — Thu, 14 Dec 2023 14:23:56 +0000

Introduction 2.0 Understanding Conditional Statements

2.1. Basic Conditional Statement
2.2. Nested Conditional Statements

3.0 FizzBuzz: A Fun Programming Exercise

3.1. The FizzBuzz Function
3.2. Using For Loop for FizzBuzz
3.3. Leveraging While Loop for FizzBuzz

4.0 Exploring For Loops

4.1. Basic For Loop Example
4.2. Applying For Loop to FizzBuzz

5.0 Unraveling While Loops

5.1. Basic While Loop Example
5.2. Adapting While Loop for FizzBuzz
6.0 Conclusion

1. Introduction

JavaScript is a versatile programming language with powerful features, and understanding conditional statements and loops is essential for effective programming. In this article, we'll dive into the basics of conditional statements and explore how to use them in practical examples. Additionally, we'll unravel the popular FizzBuzz problem using different loop structures.

2. Understanding Conditional Statements

Conditional statements are crucial for decision-making in programming. The else-if statement allows you to chain multiple conditions, providing alternative code blocks to execute based on different scenarios. Let's break down the provided code example that evaluates your last score and provides feedback on your performance for a better understanding.

2.1 Basic Conditional Statement

var score = prompt("enter your last score");

if (score > 50 && score <= 80) {
    alert("well above average");
} else if (score > 80 && score <= 90) {
    alert("Excellent performance");
} else if (score > 100) {
    alert("You are a genius");
} else {
    alert("You need to work harder");
}

Interpretation

If the score is between 50 and 80, the alert will display "Well above average."
If the score is between 80 and 90, the alert will display "Excellent performance."
If the score is above 100, the alert will praise with "You are a genius."
If none of the above conditions are met, the default is "You need to work harder."

2.2 Nested Conditional Statements

Nested conditional statements allow for more complex decision-making. In the FizzBuzz examples, you'll see nested conditions based on divisibility.

3 FizzBuzz: A Fun Programming Exercise

FizzBuzz is a classic programming problem that involves printing numbers from 1 to 100. For multiples of 3, print "Fizz"; for multiples of 5, print "Buzz"; and for numbers divisible by both 3 and 5, print "FizzBuzz."

3.1 The FizzBuzz Function

var output = []
var count = 1;

function fizzbuzz(){
    if(count % 3 ===0 && count % 5 === 0){
        output.push("fizzbuzz")
    }
    else if(count % 5 === 0){
        output.push("buzz")
    }
    else if(count % 3 === 0){
        output.push("fizz")
    }

    else{
        output.push(count);
    }
        count++
        console.log(output)


}
fizzbuzz()

In this code, the fizzbuzz function generates an output array based on the FizzBuzz logic. Numbers are pushed into the array unless they are divisible by 3, 5, or both, in which case "Fizz," "Buzz," or "FizzBuzz" is pushed, respectively.

3.2 Using For Loop for FizzBuzz

function fizzBuzz(){
    for(count =1; count<=100; count++){
        if(count % 3 ===0 && count % 5 === 0){
            output.push("fizzbuzz")
        }
        else if(count % 5 === 0){
            output.push("buzz")
        }
        else if(count % 3 === 0){
            output.push("fizz")
        }

        else{
            output.push(count);
        }

    }

        console.log(output)
}
fizzBuzz()

Utilizing a for loop, this code efficiently generates the FizzBuzz sequence and logs the result.

3.3 Leveraging While Loop for FizzBuzz

var output = []
function fizzBuzz(){
    while(count <= 100){
        if(count % 3 ===0 && count % 5 === 0){
            output.push("fizzbuzz")
        }
        else if(count % 5 === 0){
            output.push("buzz")
        }
        else if(count % 3 === 0){
            output.push("fizz")
        }

        else{
            output.push(count);
        }
            count++
    }

        console.log(output)
}
fizzBuzz()

Here, a while loop achieves the same FizzBuzz result through a different iteration approach.

4. Exploring For Loops

For loops are excellent for iterating over a sequence of numbers or elements. Let's explore a basic example and apply it to the FizzBuzz problem.

4.1 Basic For Loop Example

for (y = 0; y < 5; y++) {
    console.log(y);
}

This simple for loop prints numbers from 0 to 4.

4.2 Applying For Loop to FizzBuzz

By integrating a for loop into FizzBuzz, we efficiently generate the sequence without explicitly incrementing the counter.

5. Unraveling While Loops

While loops continue iterating until a specified condition is false. Let's examine a basic while loop and adapt it for FizzBuzz.

5.1 Basic While Loop Example

var x = 1;
while (x < 5) {
    console.log(x);
    x++;
}

This while loop prints numbers from 1 to 4.

5.2 Adapting While Loop for FizzBuzz

The while loop seamlessly accommodates the FizzBuzz logic, providing an alternative approach to the problem as shown in 3.3.

6 Conclusion

Mastering conditional statements and loops is fundamental to becoming proficient in JavaScript programming. Through practical examples like the FizzBuzz problem, you've gained insights into applying these concepts in real-world scenarios. Continue experimenting and honing your skills to become a more adept JavaScript developer. Happy Christmas!

Understanding Functions and Methods in JavaScript

Achilonu Chinwendu Faustina — Wed, 13 Dec 2023 11:35:44 +0000

Introduction
Functions in JavaScript
a. Declaration and Syntax
b. Parameters and Return Values
c. Scope
Methods in JavaScript
a. Definition and Usage
b. Invoking Methods
c. Context Binding
Differences Between Functions and Methods
a. Context
b. Invocation
c. Usage
Conclusion

1. Introduction

JavaScript, as a versatile and dynamic programming language, relies heavily on functions and methods for executing tasks and managing data. While both functions and methods play crucial roles in JavaScript, they differ in their definitions, usage, and invocation.

2. Functions in JavaScript

a. Declaration and Syntax
In JavaScript, a function is a reusable block of code designed to perform a specific task. Functions can be declared using the function keyword, followed by a name and a block of code.

function greet(name) {
    console.log(`Hello, ${name}!`);
}

b. Parameters and Return Values

Functions can accept parameters, enabling dynamic behavior based on inputs. Additionally, they can return values to the calling code.

function add(a, b) {
    return a + b;
}

let result = add(3, 5); // result is now 8

c. Scope

Functions in JavaScript have their own scope, meaning variables declared within a function are local to that function and do not affect the outer scope.

3. Methods in JavaScript

a. Definition and Usage

Methods are functions that are associated with objects. In JavaScript, objects have properties and methods. Methods are functions defined as properties of an object.

let car = {
    brand: 'Toyota',
    model: 'Camry',
    start: function() {
        console.log('Engine started.');
    }
};

b. Invoking Methods

Methods are invoked using the dot notation on the object they belong to.

car.start(); // Outputs: Engine started.

c. Context Binding

One crucial aspect of methods is that they have a reference to the object they belong to. This reference is often referred to as the 'this' keyword, which points to the object instance when the method is invoked.

let person = {
    name: 'John',
    greet: function() {
        console.log(`Hello, ${this.name}!`);
    }
};

person.greet(); // Outputs: Hello, John!

4. Differences Between Functions and Methods

a. Context
Functions are standalone entities, while methods are associated with objects and have a context (this) tied to the object.

b. Invocation
Functions are invoked independently, whereas methods are called on objects using dot notation.

c. Usage
Functions are general-purpose, while methods are specific to the objects they are attached to, often operating on the object's data.

5. Conclusion

Understanding the distinctions between functions and methods in JavaScript is fundamental to writing effective and organized code. Functions provide modularity and code reusability, while methods bring a level of organization and encapsulation within objects. By comprehending their differences, developers can leverage both functions and methods efficiently to build robust and maintainable JavaScript applications.

CODE DESCRIPTION/REVIEW

Achilonu Chinwendu Faustina — Sat, 18 Feb 2023 02:10:22 +0000

The capacity to practice and provide a description or review of codes gives you an advantage in your learning process and also a chance to improve.
I'll be giving a description of blocks of code today, and I've shared pictures of them below.

The following id were grabbed from html:

add-item-btn
item-input
list.
An EventListener was added to the addItemBtn such that when triggered, the function at the eventListener pushes the value typed in the ItemInput into the shoppingList which was given an empty array. Again it calls out the render function (render() ) while the render function (function render() ) iterates through the array and creates html for each item on the shoppingList.

DAY 10 OF CODE CHALLENGE

Achilonu Chinwendu Faustina — Fri, 30 Sep 2022 20:16:02 +0000

VALID NUMBER

DESCRIPTION OF QUESTION

A valid number can be split up into these components (in order):

A decimal number or an integer.
(Optional) An 'e' or 'E', followed by an integer.
A decimal number can be split up into these components (in order):

(Optional) A sign character (either '+' or '-').
One of the following formats:
One or more digits, followed by a dot '.'.
One or more digits, followed by a dot '.', followed by one or more digits.
A dot '.', followed by one or more digits.
An integer can be split up into these components (in order):

(Optional) A sign character (either '+' or '-').
One or more digits.
For example, all the following are valid numbers: ["2", "0089", "-0.1", "+3.14", "4.", "-.9", "2e10", "-90E3", "3e+7", "+6e-1", "53.5e93", "-123.456e789"], while the following are not valid numbers: ["abc", "1a", "1e", "e3", "99e2.5", "--6", "-+3", "95a54e53"].

Given a string x, return true if x is a valid number.

Example 1:

Input: x = "0"
Output: true
Example 2:

Input: x = "e"
Output: false
Example 3:

Input: x = "."
Output: false

PROCEDURE

I made list of possible error conditions and checked for each one which include:

Seeing an 'e'/'E' when a number has not yet been seen or more than one exponent character ('e'/'E').
When there is more than one sign or sign appearing after a decimal or number have been seen.
When decimal appeared after an 'e'/'E' has been seen or more than one decimal.
Appearance of any other non-number character.
When the end of x is reached without active number.

The above were achieved by setting some boolen flags for the different things being kept on track (exp, num, dec, sign).

OUTCOME

DAY 9 CODE CHALLENGE

Achilonu Chinwendu Faustina — Thu, 29 Sep 2022 20:14:34 +0000

MERGE k SORTED LISTS

An array of k linked-lists "lists", was given, of which each linked-list was sorted in ascending order. We were asked to merge all the linked-lists into one sorted linked-list and return it as shown in the given example below:

PROCEDURE

I merged two lists at a time and pushed to the array until lists.length === 1 and returned into the array. For instance, if: x = 1 -> 4 -> 5 y = 1 -> 3 -> 4 mergedXY = 1 -> 1 -> 3 -> 4 -> 4 ->5

(push mergedXY to the array)

we now have lists = [2 -> 6
1 -> 1 -> 3 -> 4 -> 4 ->5]

(the merging was repeated again)

x = 2 -> 6
y = 1 -> 1 -> 3 -> 4 -> 4 ->5
mergedXY = 1 -> 1 -> 2-> 3 -> 4 -> 4 ->5 -> 6

(And this was pushed to the array)

lists = [1 -> 1 -> 2-> 3 -> 4 -> 4 ->5 -> 6]

The above was returned.

CODE
var mergeKLists = function(lists) { if(lists.length ===0){ return null; } while(lists.length>1){ let x = lists.shift(); let y = lists.shift(); let mergedXY = mergeList(x,y); lists.push(mergedXY); } return lists[0] };

OUTCOME

DAY 8 CODE CHALLENGE

Achilonu Chinwendu Faustina — Wed, 28 Sep 2022 19:39:43 +0000

COMBINE TWO TABLES

Two tables were given to write an SQL query to report the firstName, lastName, city and state of each person in the "person" table. We were asked to report null if the address of a personId was not present in the "Address" table. Also, we were permitted to return result table in any order.

DIAGRAMS OF THE TABLES

PROCEDURE

From the information given above, left join is required for this solution because we are returning every details from the first(left) table and matched records from the second(right) table.
Using the select statement, select the column names (firstName, lastName, city, and state) that were stated to appear in our outcome as seen below:
select firstName, lastName, city, state
Select from the first(left) table (that is the one we are returning the all their records) as seen below:
from Person
Left join to the second(right) table using the first and second tables' common field as seen below:
left join Address using(personId)
Since we were permitted to return in any order, I would prefer we go by lastName as seen below:
order by lastName;

OUTCOME

DAY 7 CODE CHALLENGE

Achilonu Chinwendu Faustina — Tue, 27 Sep 2022 21:34:41 +0000

UTF-8 VALIDATION

An integer array "data" representing the data was given to return whether it was a valid UTF-8 encoding. That is, if it translates to a sequence of valid UTF-8 encoded characters.

PROCEDURE

Track pendingBytes by starting with zero value.
Iterate through the input data, convert 1 to 00000001.
If the pendingBytes equalizes to zero(0) at the same time with the first value in byte array (byte[0]), continue.
Using the loop, iterate through the bit of byte, it must start with 1, if bit is not equal to 1, break and increment pendingBytes.

NOTES
If starting, it needs to be > 1, 10 is only for following bytes.
secondly, if greater than 4, it is also invalid.
Lastly, a character in UTF-8 can be from 1 to 4 bytes long.

Therefore, if pendingBytes is less than or equal to 1 or greater than 4, return false and decrease pendingBytes.
If the first value in byte array equalizes to "1" and second value equalizes to "0", pendingBytes is decreased while we jump over one iteration in the loop and return false.
If none pending, it is valid, therefore we return pendingBytes to equalize zero (0).

OUTCOME

DAY 6 CODE CHALLENGE

Achilonu Chinwendu Faustina — Mon, 26 Sep 2022 21:15:28 +0000

FIZZ BUZZ MULTITHREADED

When I noticed JavaScript was not among the languages for today's challenge, I almost gave up but on a second thought, I decided to finish up the race as no knowledge was a waste. Today's challenge was all about Fizz Buzz Multithreaded and Python3 was used to solve this particular Challenge.

PROCEDURE BY BARRIER
Each every thread was apportioned its own loop 1 to n. The loops were advanced in sync using a Barrier whereby holding on for the four (4) threads to extend the barrier before unblocking all the threads. And at that juncture, the loop will carry on while the next number will now be processed by all the four (4) threads while the program will hold back for all the threads to reach the Barrier.

OUTCOME

DAY 5 CODE CHALLENGE

Achilonu Chinwendu Faustina — Sun, 25 Sep 2022 20:43:52 +0000

SORT CHARACTERS BY FREQUENCY

A string s= tree is given to rearrange in decreasing order of frequency such that, the output will be "eetr" or "eert".

APPROACH
Check the frequency of the characters;
e = 2;
t = 1;
r = 1;
writing this in decreasing order of frequency;
output = eetr
or
output = eert
Here r and t are of the same frequency, therefore anyone can be written first.

PROCEDURE

I saved the frequencies in a hashtable.
I sorted them (frequencies) in decreasing order.
I rebuilt the strings based on frequencies.

OUTCOME

DAY 4 CODE CHALLENGE

Achilonu Chinwendu Faustina — Sat, 24 Sep 2022 22:27:23 +0000

PRINT IN ORDER

Todays challenge was a very daunting one, I migrated from JavaScript to Python3 because of the unavailability of 'print in order' LeetCode problem in JavaScript version. Having started my coding career with python before I drifted to JavaScript I was able to scale through this challenge.

QUESTION
Suppose we have a class:
public class Foo{ public void first() {print("first");} public void second() {print("first");} public void third() {print("first");} }
Here, Foo will be passed to three different threads:
Thread A = first()
Thread B = second()
Thread C = third()

TASK
Design a mechanism and modify the program to ensure that the second() is executed after the first() and the third is executed after the second().

PROCEDURE
Lock method was applied to solve this problem. I started with two locked locks, whereby first thread unlocks the first lock that the second thread was waiting on while the second thread unlocks the second lock that the third thread was waiting on

OUTCOME

DAY 3 CODE CHALLENGE (PALINDROME INTEGER)

Achilonu Chinwendu Faustina — Fri, 23 Sep 2022 11:54:14 +0000

PALINDROME INTEGER

In our challenge today, we were asked to identify if a given integer is Palindrome or not. To solve any challenge, one most be willing to understand the question before execution. Let's move to the question of the day.

QUESTION AND EXPLANATION
Given an integer x, return true if x is palindrome integer.

One might wonder what a palindrome integer is but wonder not.
An integer is said to be palindrome when it reads the same both forward and backward. For example, 242 is palindrome while 148 is not. Let us also look at the following examples below:

Example 1
input: x = 242
output: true
Here output is true because from right to left also reads 242.

Example 2
input: x = -242
output: false
Reason: From left to right reads -242 while from right to left reads 242-, making it non palindrome.

Example 3
input: x = 10
output: false
This is because from right to left reads 01, which implies it not palindrome.

PROCEDURE

-Set backward to input x, convert to string, split and reverse it, then join as illustrated below.

let backward = x.toString().split('').reverse().join('')

Compare the backward string to input x and return as shown below.

return(x.string() === backward)

RESULT OUTPUT

#14G10DaysCodeChallenge(Day2: Remove Element)

Achilonu Chinwendu Faustina — Thu, 22 Sep 2022 10:44:51 +0000

REMOVE OCCURRENES OF ELEMENT IN A GIVEN ARRAY

An array of nums and value was given to remove all instances of that value in-place, to return the new length. An instruction was given to allocate extra space for another array by modifying the input array in-place with 0(1) extra memory.
For example in input, nums = [4, 1, 2, 4] and val = 4;
expected output: nums = [1,2].

PROCEDURE

-Create indicator variable starting at zero (0) to keep track.

Iterate through every element in the array using the 'for loop'. If the current value is not equal 'val'; we set nums[indicator] to nums[i] and increment indicator.

For instance, in the given example above where we have the input, nums = [4, 1, 2, 4]. If we iterate through this, nums[0] = val, it is been skipped while we move to nums[1] which is not equal to 'val' making it to be qualified to what we want, it's been moved to the front because our indicator started with zero (0). Same is applicable to nums[2], it will also be shifted forward.

Return indicator.

DEV Community: Achilonu Chinwendu Faustina

Mastering Conditional Statements, Loops, and FizzBuzz in JavaScript

Table of Contents

1. Introduction

2. Understanding Conditional Statements

2.1 Basic Conditional Statement

2.2 Nested Conditional Statements

3 FizzBuzz: A Fun Programming Exercise

3.1 The FizzBuzz Function

3.2 Using For Loop for FizzBuzz

3.3 Leveraging While Loop for FizzBuzz

4. Exploring For Loops

4.1 Basic For Loop Example

4.2 Applying For Loop to FizzBuzz

5. Unraveling While Loops

5.1 Basic While Loop Example

5.2 Adapting While Loop for FizzBuzz

6 Conclusion

Understanding Functions and Methods in JavaScript

Table of Contents

1. Introduction

2. Functions in JavaScript

b. Parameters and Return Values

c. Scope

3. Methods in JavaScript

a. Definition and Usage

b. Invoking Methods

c. Context Binding

4. Differences Between Functions and Methods

5. Conclusion

CODE DESCRIPTION/REVIEW

DAY 10 OF CODE CHALLENGE

VALID NUMBER

DAY 9 CODE CHALLENGE

MERGE k SORTED LISTS

DAY 8 CODE CHALLENGE

COMBINE TWO TABLES

DAY 7 CODE CHALLENGE

UTF-8 VALIDATION

DAY 6 CODE CHALLENGE

FIZZ BUZZ MULTITHREADED

DAY 5 CODE CHALLENGE

SORT CHARACTERS BY FREQUENCY

DAY 4 CODE CHALLENGE

PRINT IN ORDER

DAY 3 CODE CHALLENGE (PALINDROME INTEGER)

PALINDROME INTEGER

#14G10DaysCodeChallenge(Day2: Remove Element)

REMOVE OCCURRENES OF ELEMENT IN A GIVEN ARRAY