70. Climbing Stairs

• categories: Code, Interview Question, leetcode, Easy
• source: https://leetcode.com/problems/climbing-stairs/
• topics: Dynamic Programming

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?

class Solution:
    def climbStairs(self, n: int) -> int:
        if n < 2:
            return 1
            
        dp = [0] * n
        dp[0] = 1
        dp[1] = 2
 
        for i in range(2, n):
            dp[i] = dp[i-1] + dp[i-2]
 
        return dp[n-1]