climbingStairs.js

//////////////////////////////////////////////Climbing Stairs/////////////////////////////////////////////////////
// You are climbing a staircase. It takes n steps to reach the top.
// Each time you can either climb 1 or 2 steps. In how many distinct ways can you climb to the top?
// Example 1:
// Input: n = 2
// Output: 2
// Explanation: There are two ways to climb to the top.
// 1. 1 step + 1 step
// 2. 2 steps
// Example 2:
//
// Input: n = 3
// Output: 3
// Explanation: There are three ways to climb to the top.
// 1. 1 step + 1 step + 1 step
// 2. 1 step + 2 steps
// 3. 2 steps + 1 step
const climbStairs = function(n, memo = {}) {
    if(n < 3) return n;
    if(!memo[n]){
        memo[n] = climbStairs(n - 1, memo) + climbStairs(n - 2, memo);
    }

    return  memo[n];
};

// console.log(climbStairs(2));
// console.log(climbStairs(3));
// console.log(climbStairs(8));
// console.log(climbStairs(42));