Prime number algo

by Rich Costello

JavaScript

function isPrime(n) {
  if(n < 2) {
    return false
  }
  for(let i = 2; 1 < Math.sqrt(n); i++) {
    if(n%i === 0) {
      return false
    }
    return true
  }
}

console.log(isPrime(1))
console.log(isPrime(5))
console.log(isPrime(23))


// Big O  linear O(sqrt(n))