Day 8 - Challenge 3 - Unique Email Addresses

Solving the Problem of Counting Unique Email Addresses in JavaScript

Introduction: 

In today's digital age, email communication is an integral part of our lives. However, dealing with unique email addresses can sometimes be challenging due to variations that arise from period usage and the '+' character. In this blog post, we will explore how to tackle the problem of counting unique email addresses using JavaScript.

Problem Statement: We are given a list of email addresses, and our task is to determine the number of unique email addresses. A unique email address consists of a local name and a domain name. The local name may contain periods ('.') and the character '+' which is ignored.

Example: 

Let's consider the following list of email addresses:

• "test.email+abc@gmail.com"
• "test.e.mail@gmail.com"
• "testemail@gmail.com"

In this case, the number of unique email addresses is 1, as all three email addresses map to the same unique address: "testemail@gmail.com".

Approach and Solution: 

To solve this problem, we need to apply the following steps using JavaScript:

1. Iterate through each email address in the list.
2. For each email address, split it into the local name and domain name using the '@' symbol.
3. Process the local name:
   • Remove all '.' characters from the local name.
   • Ignore all characters after the '+' character.
4. Concatenate the modified local name with the domain name to form the unique email address.
5. Use a Set data structure to keep track of unique email addresses.
6. Count the number of elements in the Set, which will give us the final count of unique email addresses.

JavaScript Code Implementation:

function countUniqueEmails(emails) {
    const uniqueEmails = new Set();
    for (const email of emails) {
        const [local, domain] = email.split('@');
        const modifiedLocal = local.replace(/\./g, '').split('+')[0];
        const uniqueEmail = `${modifiedLocal}@${domain}`;
        uniqueEmails.add(uniqueEmail);
    }
    return uniqueEmails.size;
}
// Example usage
const emailList = [
    "test.email+abc@gmail.com",
    "test.e.mail@gmail.com",
    "testemail@gmail.com"
];
const uniqueCount = countUniqueEmails(emailList);
console.log("Number of unique email addresses:", uniqueCount); // Output: 1

Conclusion: 

In this blog post, we addressed the challenge of counting unique email addresses that arise from variations in the local name due to periods and the '+' character. By following a step-by-step approach and implementing the solution using JavaScript, we were able to accurately determine the number of unique email addresses in a given list. This solution showcases the power of JavaScript in solving real-world problems efficiently.

Now write the same program in your favorite language in comment section. 

Other Challenges:

1. Day 6 Challenges 
2. Day 7 Challenges
3. Day 8 Challenges