Sum All Primes

sumPrimes.js

function sumPrimes(num) {
  var sum = 0;
  var div = 0;
  var divCounter = 0;
  for (var i=2;i<=num;i++){
    if (isPrime(i) === true){
      sum = sum + i;
    }
  }
  function isPrime(n){
    var isDivisible = false;
    divCounter = 0;
    for (var j=1;j<=n;j++){
      div = Math.abs(n%j);
      if (div > 0){
        divCounter = divCounter;
      }else{
        divCounter = divCounter + 1;
      }
    }
    if (divCounter <= 2){
      return true;
    }else{
      return false;
    }
    return false;
  }
  // return isPrime(num);
  return sum;
}

sumPrimes(977);

SumPrimes.markdown

Sum All Primes

Sums all the prime numbers up to and including the provided number. A prime number is defined as having only two divisors, 1 and itself. For example, 2 is a prime number because it's only divisible by 1 and 2. 1 isn't a prime number, because it's only divisible by itself. The provided number may not be a prime.

A script by V.

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