learn_example/Dynamic programming/Fibonacci_Cycle.ts

const Fibonacci_Cycle = (n: number): number => {
  if (n <= 0) return 0;
  if (n === 1) return n;

  let n1 = 0;
  let n2 = 0;
  let n3 = 0;

  for (let index = 0; index <= n; index++) {
    if (index === 1) {
      n1 = 0;
      n2 = 1;

      continue;
    }

    n3 = n1 + n2;
    n1 = n2;
    n2 = n3;
  }

  return n3;
};

console.log(Fibonacci_Cycle(6));