{ "data": { "question": { "questionId": "2415", "questionFrontendId": "2338", "boundTopicId": null, "title": "Count the Number of Ideal Arrays", "titleSlug": "count-the-number-of-ideal-arrays", "content": "

You are given two integers n and maxValue, which are used to describe an ideal array.

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A 0-indexed integer array arr of length n is considered ideal if the following conditions hold:

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Return the number of distinct ideal arrays of length n. Since the answer may be very large, return it modulo 109 + 7.

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Example 1:

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\nInput: n = 2, maxValue = 5\nOutput: 10\nExplanation: The following are the possible ideal arrays:\n- Arrays starting with the value 1 (5 arrays): [1,1], [1,2], [1,3], [1,4], [1,5]\n- Arrays starting with the value 2 (2 arrays): [2,2], [2,4]\n- Arrays starting with the value 3 (1 array): [3,3]\n- Arrays starting with the value 4 (1 array): [4,4]\n- Arrays starting with the value 5 (1 array): [5,5]\nThere are a total of 5 + 2 + 1 + 1 + 1 = 10 distinct ideal arrays.\n
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Example 2:

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\nInput: n = 5, maxValue = 3\nOutput: 11\nExplanation: The following are the possible ideal arrays:\n- Arrays starting with the value 1 (9 arrays): \n   - With no other distinct values (1 array): [1,1,1,1,1] \n   - With 2nd distinct value 2 (4 arrays): [1,1,1,1,2], [1,1,1,2,2], [1,1,2,2,2], [1,2,2,2,2]\n   - With 2nd distinct value 3 (4 arrays): [1,1,1,1,3], [1,1,1,3,3], [1,1,3,3,3], [1,3,3,3,3]\n- Arrays starting with the value 2 (1 array): [2,2,2,2,2]\n- Arrays starting with the value 3 (1 array): [3,3,3,3,3]\nThere are a total of 9 + 1 + 1 = 11 distinct ideal arrays.\n
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Constraints:

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