sum of all prime numbers below a given number in javascript code example

Example 1: sum prime numbers javascript

function sumPrimes(num) {
  let i = 1;
  let sum = 0;
  while (i <= num) {
    if (isPrime(i)) {
      sum += i;
    }
    i++;
  }
  return sum;
}
//function to check if a number is prime or not
function isPrime(x) {
  for (let i = 2; i < x; i++) {
    if (x % i === 0) return false;
  }
  return x !== 1 && x !== 0;
}
//test here
sumPrimes(10);

Example 2: sum of all primes below 2 javascript

function sumPrimes(num) {

    let sum = 0;

    const isPrime = n => {
        for (let i = 2; i < n; i++)
            if (n % i === 0) return false;
        return n !== 1;
    }

    for (i = 2; i <= num; i++) {
        if (isPrime(i)) {
            sum += i;
            console.log(i);
            console.log(isPrime(i));
        }
    }

    console.log(sum);
    return sum;
}

// test here
sumPrimes(10);