/**
 * @function ClimbStairs
 * @description You are climbing a stair case. It takes n steps to reach to the top.Each time you can either climb 1 or 2 steps. In how many distinct ways can you climb to the top?
 * @param {Integer} n - The input integer
 * @return {Integer} distinct ways can you climb to the top.
 * @see [Climb_Stairs](https://www.geeksforgeeks.org/count-ways-reach-nth-stair/)
 */

const climbStairs = (n) => {
  let prev = 0
  let cur = 1
  let temp

  for (let i = 0; i < n; i++) {
    temp = prev
    prev = cur
    cur += temp
  }
  return cur
}

export { climbStairs }