{ "data": { "question": { "questionId": "1299", "questionFrontendId": "1191", "boundTopicId": null, "title": "K-Concatenation Maximum Sum", "titleSlug": "k-concatenation-maximum-sum", "content": "

Given an integer array arr and an integer k, modify the array by repeating it k times.

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For example, if arr = [1, 2] and k = 3 then the modified array will be [1, 2, 1, 2, 1, 2].

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Return the maximum sub-array sum in the modified array. Note that the length of the sub-array can be 0 and its sum in that case is 0.

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As the answer can be very large, return the answer modulo 109 + 7.

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Example 1:

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\nInput: arr = [1,2], k = 3\nOutput: 9\n
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Example 2:

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\nInput: arr = [1,-2,1], k = 5\nOutput: 2\n
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Example 3:

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\nInput: arr = [-1,-2], k = 7\nOutput: 0\n
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Constraints:

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C# 10 with .NET 6 runtime

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