Count ways to reach nth stair
Detailed guide and Python implementation for the 'Count ways to reach nth stair' problem.
Problem Statement
Write a function count_ways_stair(n) that returns the number of distinct ways to climb n stairs. Each time you can either climb 1 or 2 steps.
- •1 <= n <= 50
Examples
count_ways_stair(3)
3
There are three ways: 1+1+1, 1+2, and 2+1.
count_ways_stair(4)
5
There are five ways: 1+1+1+1, 1+1+2, 1+2+1, 2+1+1, 2+2.
Need a Hint?
Edge Cases to Watch
- Empty input structures
- Single element inputs
- Large numerical bounds
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