Climbing Stairs

Problem

Return the number of distinct ways to climb a staircase of n steps when each move is either 1 or 2 steps.

The count follows the Fibonacci recurrence ways(n) = ways(n-1) + ways(n-2) with ways(0) = 1 and ways(1) = 1. Assume n >= 0.

Hint

The number of ways to reach step n equals the ways to reach n-1 plus the ways to reach n-2.

case 1

in: [1]

expected: 1

case 2

in: [2]

expected: 2

case 3

in: [3]

expected: 3

case 4

in: [5]

expected: 8

case 5

in: [10]

expected: 89

Starter codePython

def climb_stairs(n):
    # Your code here
    pass

5 test cases · run your code against them in the editor