Climbing Stairs
Updated Jan 31, 2026
Problem
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?
Constraints
1 <= n <= 45
Examples
Example 1
Input:
n = 2
Output:
2
There are two ways to climb to the top: 1. 1 step + 1 step, 2. 2 steps
Example 2
Input:
n = 3
Output:
3
There are three ways: 1. 1+1+1, 2. 1+2, 3. 2+1
Function Signature
def climbStairs(self, n: int) -> int
How to Submit
Implement a Solution class with a climbStairs method.
Your method will be called with the input parameters and should return the answer.