01. Print N-th Element

function nthEl(arr) {
  let lastNum = arr.pop();
  let resultArr = [];
  for (let i in arr) {
    if (i % lastNum === 0) {
      resultArr.push(arr[i]);
    }
  }
  console.log(resultArr.join(" "));
}
nthEl(["5", "20", "31", "4", "20", "2"]);