{ "data": { "question": { "questionId": "3414", "questionFrontendId": "3154", "categoryTitle": "Algorithms", "boundTopicId": 2782785, "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.

\n\n

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:

\n\n\n\n

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

\n\n

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

\n\n

 

\n

Example 1:

\n\n
\n

Input: k = 0

\n\n

Output: 2

\n\n

Explanation:

\n\n

The 2 possible ways of reaching stair 0 are:

\n\n\n
\n\n

Example 2:

\n\n
\n

Input: k = 1

\n\n

Output: 4

\n\n

Explanation:

\n\n

The 4 possible ways of reaching stair 1 are:

\n\n\n
\n\n

 

\n

Constraints:

\n\n\n", "translatedTitle": "到达第 K 级台阶的方案数", "translatedContent": "

给你有一个 非负 整数 k 。有一个无限长度的台阶,最低 一层编号为 0 。

\n\n

虎老师有一个整数 jump ,一开始值为 0 。虎老师从台阶 1 开始,虎老师可以使用 任意 次操作,目标是到达第 k 级台阶。假设虎老师位于台阶 i ,一次 操作 中,虎老师可以:

\n\n\n\n

请你返回虎老师到达台阶 k 处的总方案数。

\n\n

注意 ,虎老师可能到达台阶 k 处后,通过一些操作重新回到台阶 k 处,这视为不同的方案。

\n\n

 

\n\n

示例 1:

\n\n
\n

输入:k = 0

\n\n

输出:2

\n\n

解释:

\n\n

2 种到达台阶 0 的方案为:

\n\n\n
\n\n

示例 2:

\n\n
\n

输入:k = 1

\n\n

输出:4

\n\n

解释:

\n\n

4 种到达台阶 1 的方案为:

\n\n\n
\n\n

 

\n\n

提示:

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