We are required to write a JavaScript function that takes in a number as the only argument. The function should find and return the sum of all the prime numbers that are smaller than n.
For example −
If n = 10, then the output should be 17, because the prime numbers upto 10 are 2, 3, 5, 7, whose sum is 17
Example
The code for this will be −
const isPrime = (num) => { let x = Math.floor(Math.sqrt(num)); let j = x; while (j >= 2) { if (num % j === 0) { return false; } j−−; } return true; }; const sumOfPrimes = (num = 10) => { let iter = num; let sum = 0; while (iter >= 2) { if (isPrime(iter) === true) { sum += iter; } iter−−; } return sum; }; console.log(sumOfPrimes(14)); console.log(sumOfPrimes(10));
Output
And the output in the console will be −
41 17 1060