Count-by-X.js

/*
  Create a function with two arguments that will return an array of the first n multiples of x.

  Assume both the given number and the number of times to count will be positive numbers greater than 0.

  Return the results as an array or list ( depending on language ).

  Examples
  countBy(1,10) === [1,2,3,4,5,6,7,8,9,10]
  countBy(2,5) === [2,4,6,8,10]
*/

// Answer:

function countBy(x, n) {
  let z = [];
  let current = 0;
  while (z.length !== n) {
   current += x 
   z.push(current)
  }

  return z;
}

// BigO: O(n)