Finding sum of all numbers within a range in JavaScript

Problem

We are required to write a JavaScript function that takes in an array that specifies a range.

Our function should find and return the sum of all the natural numbers falling in the range including the range numbers.

Example

Following is the code −

 Live Demo

const range = [4, 67];
const findSum = ([l, h]) => {
   let sum = 0;
   for(let i = l; i <= h; i++){
      sum += i;
   };
   return sum;
};
console.log(findSum(range));

Output

Following is the console output −

2272