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Climbing Stairs - Leetcode 70 - Python - Dynamic Programming

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





class Solution:

    def climbStairs(self, n: int) -> int:

        f,s = 1, 1

        for i in range(n-1):

            t = f

            f = f + s

            s = t

        return f



Explaination :





 

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