#P11059. [2016杭电多校]To My Girlfriend

[2016杭电多校]To My Girlfriend

To My Girlfriend

Problem Description

Dear Guo I never forget the moment I met with you.You carefully asked me: "I have a very difficult problem. Can you teach me?".I replied with a smile, "of course"."I have n items, their weight was a[i]",you said,"Let's define f(i,j,k,l,m) to be the number of the subset of the weight of n items was m in total and has No.i and No.j items without No.k and No.l items.""And then," I asked.You said:"I want to know

$$\sum_{i=1}^{n}\sum_{j=1}^{n}\sum_{k=1}^{n}\sum_{l=1}^{n}\sum_{m=1}^{s}f(i,j,k,l,m)\quad (i,j,k,l\quad are\quad different) $$

Sincerely yours, Liao

Input

The first line of input contains an integer T(T15)(T\le 15) indicating the number of test cases. Each case contains 2 integers nn, ss (4n1000,1s1000)(4\le n\le 1000,1\le s\le 1000). The next line contains n numbers: a1,a2,,ana_1,a_2,\dots,a_n (1ai1000)(1\le a_i\le 1000).

Output

Each case print the only number — the number of her would modulo 109+710^9+7 (both Liao and Guo like the number).

Sample Input

2
4 4
1 2 3 4
4 4
1 2 3 4

Sample Output

8
8

Author

UESTC

Source

2016 Multi-University Training Contest 6