
Challenge Statement
- You are climbing a staircase. It takes
n
steps to reach the top. - Each time you can either climb
1
or2
steps. In how many distinct ways can you climb to the top? - This challenge corresponds to LeetCode #70.
Constraints
1 <= n <= 45
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
Solution
Below is my solution and some test cases. This solution has a linear time complexity O(n) and a linear space complexity O(n), where n is the number of steps.