{ "data": { "question": { "questionId": "1398", "questionFrontendId": "1269", "boundTopicId": null, "title": "Number of Ways to Stay in the Same Place After Some Steps", "titleSlug": "number-of-ways-to-stay-in-the-same-place-after-some-steps", "content": "

You have a pointer at index 0 in an array of size arrLen. At each step, you can move 1 position to the left, 1 position to the right in the array, or stay in the same place (The pointer should not be placed outside the array at any time).

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Given two integers steps and arrLen, return the number of ways such that your pointer still at index 0 after exactly steps steps. Since the answer may be too large, return it modulo 109 + 7.

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Example 1:

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\nInput: steps = 3, arrLen = 2\nOutput: 4\nExplanation: There are 4 differents ways to stay at index 0 after 3 steps.\nRight, Left, Stay\nStay, Right, Left\nRight, Stay, Left\nStay, Stay, Stay\n
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Example 2:

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\nInput: steps = 2, arrLen = 4\nOutput: 2\nExplanation: There are 2 differents ways to stay at index 0 after 2 steps\nRight, Left\nStay, Stay\n
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Example 3:

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\nInput: steps = 4, arrLen = 2\nOutput: 8\n
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Constraints:

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Most standard library headers are already included automatically for your convenience.

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