JavaScript Challenges for Beginners with Solutions
For coders-to-be, JavaScript challenge problems are an engaging and efficient method of learning. They take theoretical notions and turn them into real-world problems to be addressed. These exercises are geared towards beginners and cover basic concepts such as variables, data types, and functions. All JavaScript challenges for beginners has a comprehensive solution so you can grasp the “why” behind the code. Begin coding and establish a solid foundation for your development journey by exploring our JavaScript course syllabus.
JavaScript Challenges and Solutions
Here are the top JavaScript challenges for beginners with coding solutions:
The “Hello, World!” Function
Challenge: Implement a function named sayHello that returns “Hello, World!”.
Solution:
- Define a function with the function keyword.
- Return the given string using the return statement.
Sample Code:
function sayHello() {
return “Hello, World!”;
}
Real-time Application: This is the basis of the first step for any programmer. It is utilized in testing environments to verify that a basic setup is functioning properly before addressing more complicated logic. A basic alert or console log in a web application is a practical example.
Simple Variable Swapping
Challenge: Exchange the contents of two variables, a and b, using no third temporary variable.
Solution:
- Swap the values using destructuring assignment in one line.
- This is a new and elegant solution.
Sample Code:
let a = 5;
let b = 10;
[a, b] = [b, a];
console.log(`a is now ${a}, and b is now ${b}`); // a is now 10, and b is now 5
Real-time Usage: Variable value swapping is a common operation in sorting algorithms (such as Bubble Sort) and data manipulation programs.
Recommended: JavaScript Course Online.
Check for Odd or Even
Challenge: Create a function isEven that passes a number as an argument and returns true if the number is even, and false if it’s odd.
Solution:
- Apply the modulo operator (%) to get the remainder when the number is divided by 2.
- If the remainder is 0, the number is even.
Sample Code:
function isEven(number) {
if (number % 2 === 0) {
return true;
} else {
return false;
}
}
console.log(isEven(4)); // true
console.log(isEven(7)); // false
Real-time Application: This is applied in a number of situations, ranging from alternating row colors in a table (in a calendar or list of items) to the logic behind game development.
Array Sum
Challenge: Implement a function sumArray that accepts an array of numbers and returns their sum.
Solution:
- Create a variable total and assign it the value 0.
- Implement a for loop to cycle through each number in the array.
- Append each number to the total.
Sample Code:
function sumArray(numbers) {
let total = 0;
for (let i = 0; i < numbers.length; i++) {
total += numbers[i];
}
return total;
}
const myNumbers = [10, 20, 30, 40];
console.log(sumArray(myNumbers)); // 100
Real-time Application: Sum calculation is a fundamental operation in data analysis, financial use cases (computing a total bill), and e-commerce (computing a shopping cart total).
Recommended: JavaScript Tutorial for Beginners.
Largest Number in an Array
Challenge: Implement a function findLargest that receives an array of numbers and returns the largest number in the array.
Solution:
- Set max equal to the first element of the array.
- Loop through the remainder of the array. If a cell is larger than max, change max.
Sample Code:
function findLargest(numbers) {
let max = numbers[0];
for (let i = 1; i < numbers.length; i++) {
if (numbers[i] > max) {
max = numbers[i];
}
}
return max;
}
const myNumbers = [5, 12, 3, 9, 20];
console.log(findLargest(myNumbers)); // 20
Real-time Application: Used in data visualization to calculate the scale of a chart, in performance metrics to identify peak use, or in online shopping to identify the costliest item.
Reverse a String
Challenge: Write a function reverseString that reverses a string and returns it.
Solution:
- Use the built-in string functions: .split(”) to get an array of characters from the string, .reverse() to reverse the array, and .join(”) to get a string from it.
Sample Code:
function reverseString(str) {
return str.split(”).reverse().join(”);
}
console.log(reverseString(“hello”)); // “olleh”
Real-time Application: Applied in making user-friendly interfaces, i.e., auto-correct features, or in data processing to reverse an array of characters for certain validation tests.
Recommended: JavaScript Interview Questions and Answers.
Filter an Array
Challenge: Define a function filterEvens that accepts an array of numbers and returns a new array with the even numbers.
Solution:
- Apply the .filter() method, an array method used to return a new array containing only elements that pass a test.
Sample Code:
function filterEvens(numbers) {
return numbers.filter(number => number % 2 === 0);
}
const myNumbers = [1, 2, 3, 4, 5, 6];
console.log(filterEvens(myNumbers)); // [2, 4, 6]
Real-time Application: Filtering is a frequent operation in web development, employed to show a particular set of data from a list, like displaying only “available” goods in a shop or “unread” messages in an inbox.
Count Vowels in a String
Challenge: Create a function countVowels that accepts a string and returns the quantity of vowels it has (a, e, i, o, u).
Solution:
- Lowercase the string.
- Use a for loop to loop over every character.
- Use an if statement to determine if the character is a vowel.
Sample Code:
function countVowels(str) {
const vowels = “aeiou”;
let count = 0;
for (const char of str.toLowerCase()) {
if (vowels.includes(char)) {
count++;
}
}
return count;
}
console.log(countVowels(“Hello World”)); // 3
Real-time Application: This logic can be applied in natural language processing (NLP) to scrutinize text, or in minor games and puzzles.
Check for Palindrome
Challenge: Create a function isPalindrome that determines whether or not a string is a palindrome (read the same forward and backward).
Solution:
- Use the reverseString logic from Challenge 6.
- Compare the original string with its reverse.
Sample Code:
function isPalindrome(str) {
const reversedStr = str.split(”).reverse().join(”);
return str.toLowerCase() === reversedStr.toLowerCase();
}
console.log(isPalindrome(“madam”)); // true
console.log(isPalindrome(“hello”)); // false
Real-time Application: Palindrome checks are applied in data validation, primarily for user input, or in developing word games and puzzles.
Recommended: Web Developer Training in Chennai.
Simple Calculator
Challenge: Define a function calculate having three arguments: num1, operator (+, -, *, /), and num2, and return the calculation result.
Solution:
- Apply a switch statement to process the various operators and then execute the corresponding operation.
Sample Code:
function calculate(num1, operator, num2) {
switch (operator) {
case ‘+’:
return num1 + num2;
case ‘-‘:
return num1 – num2;
case ‘*’:
return num1 * num2;
case ‘/’:
return num1 / num2;
default:
return “Invalid operator”;
}
}
console.log(calculate(10, ‘+’, 5)); // 15
console.log(calculate(8, ‘*’, 4)); // 32
Real-time Application: This is the core of any calculator application, ranging from a simple web app to a more sophisticated desktop one. It’s a straightforward example of applying conditional logic to carry out various actions based on an input provided.
Explore: All Software Training Courses in Chennai.
Conclusion
By overcoming these JavaScript challenges for beginners, you’ve acquired real-world experience with fundamental programming principles. This hands-on training gives confidence and a thorough knowledge of the language, abilities that are critical to any web developer. To further your education and become proficient in advanced concepts such as DOM manipulation and asynchronous programming, take our in-depth JavaScript course in Chennai.