13.js

// Return the next higher prime number

// This challenge is a little bit more complex
// Write a function that takes a number as argument
// If the number is prime, return the number
// If not, return the next higher prime number

function myFunction(num) {
  let counter = 0;
  do {
    counter = 0;
    for (let i = 2; i <= num; i++) {
      if (num % i === 0) counter++;
    }
    num++;
  } while (counter > 1);
  return num - 1;
}

// AUTHOR'S:
// function myFunction( input ) {
//   function isPrime(num) {
//     for (let i = 2; i <= Math.sqrt(num); i++) {
//       if (num % i === 0) return false;
//     }
//     return num > 1;
//   }
//  let n = input;
//  while (!isPrime(n)) n++;
// return n
// }

console.log(myFunction(38)); // 41
console.log(myFunction(7)); // 7
console.log(myFunction(115)); // 127
console.log(myFunction(2000)); // 2003