Looking for prime numbers in array to store in another array in Javascript

user_16451412 0
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I was attempting to build a program to look through an array, grab any prime numbers, and then store them in a separate array. I have tried to mix and match some code pieces, it seems to work for the most part, but will sometimes give a non-prime number (in this case 33, divisible by 3 and 11). All of the other numbers seem to be correct. Could it be something small I am missing? Any and all help is appreciated. Thank you!

var array = [33,23,5,7,10,20,30,12,37];
primes(array);



function primes(arr){
    var arrayLength = arr.length;
    var primeArray = [];

    function primeNum(arrElement){
        if (arrElement <= 1){
            console.log(arrElement + " is not a valid test number.");
        }
        for (var x = 2; x < arrElement; x++){
            if (arrElement % x === 0){
                return false;
            }
            return true;
        }
    
    }

    for (var y = 0; y <= arrayLength - 1; y++){
        if(primeNum(arr[y])){
            primeArray.push(arr[y]);
        }
    }
    console.log(primeArray);
    }

Output is giving: (5) [33, 23, 5, 7, 37]

arrays javascript
1 Answers

var array = [33, 23, 5, 7, 10, 20, 30, 12, 37];
primes(array);



function primes(arr) {
  var arrayLength = arr.length;
  var primeArray = [];

  function primeNum(arrElement) {
    if (arrElement <= 1) {
      console.log(arrElement + " is not a valid test number.");
    }
    for (var x = 2; x < arrElement; x++) {
      if (arrElement % x === 0) {
        return false;
      }
    }
    return true;
  }

  for (var y = 0; y <= arrayLength - 1; y++) {
    if (primeNum(arr[y])) {
      primeArray.push(arr[y]);
    }
  }
  console.log(primeArray);
}

In funcation primeNum the return true should Outside the for loop.

user_155034240
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