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Let's call a sequence of integers a1, a2, ..., aN _almost monotonic_ if first |
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K elements are non-decreasing sequence and last N-K+1 elements are non- |
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increasing sequence: a1≤a2≤...≤aK and aK≥aK+1≥...≥aN. |
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The _diversity number_ of a sequence a1, a2, ..., aN is the number of possible |
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sequences b1, b2,..., bN for which 0≤bi<ai and all of the numbers b1, b2,..., |
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bN are different. The diversity number of an empty sequence is 1. |
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You need to find the sum of the diversity numbers of all almost monotonic |
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subsequences of a sequence. Since this number can be very large, find it |
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modulo 1,000,000,007. A subsequence is a sequence that can be obtained from |
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another sequence by deleting some elements without changing the order of the |
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remaining elements. Two sequences are considered different if their lengths |
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differ or there is at least one position at which they differ. |
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## Input |
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The first line of the input file consists of a single number **T**, the number |
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of test cases. Each test case consists of a number **M**, the number of |
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elements in a sequence, followed by **M** numbers **n**, elements of some |
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sequence (note that this sequence is not necessarily _almost monotonic_). All |
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tokens are whitespace-separated |
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## Constraints |
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**T** = 20 |
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1 ≤ **M**, **n** ≤ 100 |
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## Output |
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Output T lines, with the answer to each test case on a single line. |
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