{ "data": { "question": { "questionId": "3414", "questionFrontendId": "3154", "boundTopicId": null, "title": "Find Number of Ways to Reach the K-th Stair", "titleSlug": "find-number-of-ways-to-reach-the-k-th-stair", "content": "

You are given a non-negative integer k. There exists a staircase with an infinite number of stairs, with the lowest stair numbered 0.

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Alice has an integer jump, with an initial value of 0. She starts on stair 1 and wants to reach stair k using any number of operations. If she is on stair i, in one operation she can:

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Return the total number of ways Alice can reach stair k.

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Note that it is possible that Alice reaches the stair k, and performs some operations to reach the stair k again.

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Example 1:

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Input: k = 0

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Output: 2

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Explanation:

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The 2 possible ways of reaching stair 0 are:

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Example 2:

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Input: k = 1

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Output: 4

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Explanation:

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The 4 possible ways of reaching stair 1 are:

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\n\n

 

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Constraints:

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