You are given an array \(A\) of length \(N\). A subsequence is called good if all the elements of that subsequence are distinct. Find the number of non-empty good subsequences modulo \(10^9+7\).
Two subsequences are different if they differ in the indices chosen.
Input Format:
- The first line contains an integer \(T\), which denotes the number of test cases.
- The first line of each test case contains an integer \(N\).
- The second line of each test case contains \(N\) space-separated integers, elements of array \(A\).
Output Format:
For each test case, print the number of non-empty good subsequences modulo \(10^9+7\).
Constraints:
2 3 2 3 1 4 1 1 1 1
7 4
First test case:
Good subsequences are \([2], [3], [1], [2, 3], [2, 1], [3, 1], [2, 3, 1]\). Hence, the answer is \(7\).
Second test case:
Good subsequences are \( [1], [1], [1], [1]\). Hence, the answer is \(4\).
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