. Day 2 - Challenge 3 - Counting Vowels in string Skip to main content

Day 2 - Challenge 3 - Counting Vowels in string

Counting Vowels in JavaScript: A Simple Problem

Are you ready to dive into a classic programming challenge? In this blog post, we'll explore a simple yet fundamental problem: counting the number of vowels in a given string using JavaScript. Whether you're new to programming or looking to refresh your skills, this problem is a great exercise to enhance your understanding of string manipulation, loops, and arrays. So, let's get started!

The Problem

Our task is to write a JavaScript program that takes a string as input and returns the count of vowels present in that string. Vowels are the letters 'a', 'e', 'i', 'o', and 'u', regardless of their case. This means that both uppercase and lowercase vowels should be considered when counting.

The Approach

To solve this problem, we can break it down into a few simple steps:

  1. Convert to Lowercase: To ensure that we count both uppercase and lowercase vowels, we should first convert the entire input string to lowercase. This way, we can work with a standardized format.

  2. Define the Vowels: Create an array that contains the vowel characters ('a', 'e', 'i', 'o', 'u'). This array will help us check whether a given character is a vowel or not.

  3. Loop Through the String: Use a loop to iterate through each character of the lowercase string.

  4. Count Vowels: Inside the loop, check if the current character exists in the vowel array. If it does, increment a counter variable to keep track of the number of vowels encountered.

  5. Return the Count: After looping through the entire string, return the final count of vowels.

The JavaScript Code

Let's take a look at the JavaScript code that implements the solution:


function countVowels(str) {
  const lowerStr = str.toLowerCase();
  const vowels = ['a', 'e', 'i', 'o', 'u'];
  let vowelCount = 0;
  
  for (let char of lowerStr) {
    if (vowels.includes(char)) {
      vowelCount++;
    }
  }
  
  return vowelCount;
}

// Example usage
const inputString = "Hello, how are you?";
const numVowels = countVowels(inputString);
console.log(`Number of vowels: ${numVowels}`);


This program defines a function called countVowels that takes a string as input and returns the count of vowels in the string. It converts the input string to lowercase to handle both uppercase and lowercase vowels. Then, it loops through each character in the string and checks if the character is a vowel using the includes method on the vowels array. If the character is a vowel, the vowelCount is incremented. Finally, the function returns the total count of vowels.

Demo

Vowel Counter

Number of vowels: 0


Testing the Solution

You can test the program with various input strings, both simple and complex. Try inputting sentences, phrases, or even paragraphs to see how the program accurately counts the vowels each time.

Conclusion

Congratulations! You've successfully tackled the "Vowel Counter" problem using JavaScript. This exercise not only helped you practice string manipulation and array usage but also encouraged you to think logically and break down a problem into manageable steps. As you continue your programming journey, remember that even seemingly simple challenges like this one play a vital role in strengthening your coding skills.

Now write the program to count vowel in your language in comments.

Complete Other Challenges: 

  1. Day 1 Challenges
  2. Day 2 Challenge 1
  3. Day 2 Challenge 2
     

Comments

Popular posts from this blog

Day 9 - Challenge 1 - Product of Array Except Self

Solving the "Product of Array Except Self" Problem in JavaScript Are you ready to dive into a common coding challenge that not only tests your programming skills but also sharpens your problem-solving mindset? If you're up for the challenge, let's tackle the "Product of Array Except Self" problem together using JavaScript. This problem requires us to return an array where each element at index i is the product of all the elements in the original array except the one at index i . Understanding the Problem:   Imagine you're given an array of integers, let's call it nums . Your task is to create a new array where the value at index i in this new array is the product of all the elements in nums , except the one at index i . In other words, you're calculating the product of all the elements to the left of nums[i] and the product of all the elements to the right of nums[i] , and then multiplying these two products to get the final value at index i ...

Day 9 - Challenge 2 - Reverse Linked List

Reversing a Singly Linked List in JavaScript: An In-Place Approach Introduction:   Singly linked lists are fundamental data structures in computer science that consist of a sequence of nodes, each containing data and a reference to the next node in the list. Reversing a singly linked list is a classic problem that challenges programmers to manipulate pointers effectively to achieve the desired outcome. In this blog post, we'll explore the problem of reversing a singly linked list using an in-place approach and provide a step-by-step solution in JavaScript. Problem Statement:   Given the head of a singly linked list, our task is to reverse the list in-place and return its new head. In other words, we need to modify the pointers of the nodes in such a way that the direction of the linked list is reversed. Solution Approach:   To solve this problem, we will iterate through the linked list while maintaining three pointers: previous , current , and next . The previous pointer...

Day 8 - Challenge 2 - Move Zeroes to the End

Moving Zeroes to the End: A JavaScript Solution Introduction:   When working with arrays, there are often times when we need to manipulate their elements to achieve a specific goal. One common problem is moving all zeroes to the end of an array while keeping the order of non-zero elements unchanged. In this blog post, we will explore an elegant solution to this problem using JavaScript. We'll discuss the problem statement, the approach we'll take, and provide a step-by-step guide to implementing the solution. The Problem:   Given an array of integers, the task is to move all zeroes to the end of the array while maintaining the relative order of the non-zero elements. This means that after rearranging the array, all the zeroes should be at the end, and the order of the non-zero elements should remain the same. The Approach:   To solve this problem, we can utilize a two-pointer approach. We'll maintain two pointers, one for iterating through the array and another for keepin...