Count Ordered One-Step and Two-Step Climbs
Company: Google
Role: Software Engineer
Category: Coding & Algorithms
Difficulty: easy
Interview Round: Other
### Problem
A staircase has `steps` steps. On each move you climb either one step or two steps. Return the number of different move sequences that land exactly at the top.
The order of moves matters: taking one step and then two is different from taking two and then one.
### Examples
**Example 1**
```text
Input: steps = 4
Output: 5
```
The move sequences are `1+1+1+1`, `1+1+2`, `1+2+1`, `2+1+1`, and `2+2`.
**Example 2**
```text
Input: steps = 5
Output: 8
```
Eight different sequences of one-step and two-step moves finish exactly five steps above the start.
### Constraints
- `1 <= steps <= 45`
Overview: Count the ordered ways to climb a staircase using moves of one or two steps, returning the total count rather than an enumeration.