Fibonacci-iterative.js

// find nth fibonacci both recursive and iterative
// 0 1 1 2 3 5 8 13 21
// 0 1 2 3 4 5 6 7  8

function fibo(nth) {
  if (nth === 0) {
    return 0;
  }
  if (nth === 1) {
    return 1;
  }
  let firstResult = 1;
  let secondResult = 0;
  let result;
  for (let i = 2; i <= nth; i++) {
    result = firstResult + secondResult;
    secondResult = firstResult;
    firstResult = result;
  }
  return result;
}
console.log(fibo(6));
console.log(fibo(7));
console.log(fibo(8));