Daily JavaScript Challenge: Find the Missing Number in Consecutive Array
Hey fellow developers! 👋 Welcome to today's JavaScript coding challenge. Let's keep those programming skills sharp!
The Challenge
Difficulty: Easy
Topic: Array
Description
Given an array containing consecutive integers from 1 to n with one integer missing, find the missing number efficiently.
Ready to Begin?
- Fork this challenge
- Write your solution
- Test it against the provided test cases
- Share your approach in the comments below!
Want to Learn More?
Check out the documentation about this topic here: https://en.wikipedia.org/wiki/Arithmetic_progression
Join the Discussion!
- How did you approach this problem?
- Did you find any interesting edge cases?
- What was your biggest learning from this challenge?
Let's learn together! Drop your thoughts and questions in the comments below. 👇
This is part of our Daily JavaScript Challenge series. Follow me for daily programming challenges and let's grow together! 🚀
Top comments (2)
nice one, always feels good to figure these out fast but i wonder if most folks lean on built-ins or just do the math themselves - you think tools like this actually help you get better or just make it easier to get by
function findMissingNumber(arr, n) {
const expectedSum = (n * (n + 1)) / 2;
const actualSum = arr.reduce((acc, num) => acc + num, 0);
return expectedSum - actualSum;
}