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KrofDrakulavs.raulbc777

Fast Primality Test in Javascript

Code
Diff
  • function isPrime(n) {
    if (n < 2)
      return false;
    // do an early exit for even numbers
    if (n == 2)
      return true;
    if (n % 2 == 0)
      return false;
    // we only have to check odd numbers, starting with 3
    for (var x = 3; x <= Math.floor(Math.sqrt(n)); x += 2)
      if (n % x == 0)
        return false;
    return true;
}
    • function isPrime(n) {
    • if (n < 2) return false;
    • for (var x = 2; x <= Math.floor(Math.sqrt(n)); x++) {if (n % x == 0) return false;}
    • if (n < 2)
    • return false;
    • // do an early exit for even numbers
    • if (n == 2)
    • return true;
    • if (n % 2 == 0)
    • return false;
    • // we only have to check odd numbers, starting with 3
    • for (var x = 3; x <= Math.floor(Math.sqrt(n)); x += 2)
    • if (n % x == 0)
    • return false;
    • return true;
    • }