Dynamic Programming · Coding problem
Climbing Stairs
A free coding problem from the DP: 1D Tabulation skill. Read it here, then solve it in the app in Java or Python.
- Easy
- Coding problem
- Free
- Java and Python
The problem
A staircase has n steps. With each stride you go up either one step or two. Count the different sequences of strides that take you from the bottom to the top.
Example
Input: n = 7
Output: 21
For instance 1 1 1 1 1 1 1, 2 2 2 1 and 1 2 2 2 are three of the 21.
Constraints
1 <= n <= 45
How it's graded
- Run checks your code against the examples. Submit also runs a hidden suite in four groups - basic cases, edge cases, random inputs and performance tests at the size limit - and shows which groups pass, never the hidden inputs.
- Stuck? Hints come in four steps, from a nudge to a code skeleton, each costing part of the points.
- Once you pass, you see the approaches from brute force to optimal, and where your solution lands among them.
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