{ "data": { "question": { "questionId": "1631", "questionFrontendId": "1524", "boundTopicId": null, "title": "Number of Sub-arrays With Odd Sum", "titleSlug": "number-of-sub-arrays-with-odd-sum", "content": "

Given an array of integers arr, return the number of subarrays with an odd sum.

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

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Example 1:

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\nInput: arr = [1,3,5]\nOutput: 4\nExplanation: All subarrays are [[1],[1,3],[1,3,5],[3],[3,5],[5]]\nAll sub-arrays sum are [1,4,9,3,8,5].\nOdd sums are [1,9,3,5] so the answer is 4.\n
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Example 2:

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\nInput: arr = [2,4,6]\nOutput: 0\nExplanation: All subarrays are [[2],[2,4],[2,4,6],[4],[4,6],[6]]\nAll sub-arrays sum are [2,6,12,4,10,6].\nAll sub-arrays have even sum and the answer is 0.\n
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Example 3:

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\nInput: arr = [1,2,3,4,5,6,7]\nOutput: 16\n
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Constraints:

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Python 2.7.12.

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C# 10 with .NET 6 runtime

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