#USACOC2113B. Do You Know Your ABCs?

Do You Know Your ABCs?

Farmer John's cows have been holding a daily online gathering on the "mooZ" video meeting platform. For fun, they have invented a simple number game to play during the meeting to keep themselves entertained.

Elsie has three positive integers AA, BB, and CC (1ABC1\leqslant A\leqslant B\leqslant C). These integers are supposed to be secret, so she will not directly reveal them to her sister Bessie. Instead, she tells Bessie NN distinct integers x1,x2,,xNx_1,x_2,\ldots,x_N, claiming that each xix_i is one of AA, BB, CC, A+BA+B, B+CB+C, C+AC+A, or A+B+CA+B+C. However, Elsie may be lying; the integers xix_i might not correspond to any valid triple (A,B,C)(A,B,C).

This is too hard for Bessie to wrap her head around, so it is up to you to determine the number of triples (A,B,C)(A,B,C) that are consistent with the numbers Elsie presented (possibly zero).

Each input file will contain TT test cases that should be solved independently.

  • 1xi1091\leqslant x_i\leqslant 10^9
  • 4N74\leqslant N\leqslant 7
  • 1T1001\leqslant T\leqslant 100

Input Format

The first input line contains TT.

Each test case starts with NN, the number of integers Elsie gives to Bessie.

The second line of each test case contains NN distinct integers x1,x2,,xNx_1,x_2,\ldots,x_N.

Output Format

For each test case, output the number of triples (A,B,C)(A,B,C) that are consistent with the numbers Elsie presented.

10
7
1 2 3 4 5 6 7
4
4 5 7 8
4
4 5 7 9
4
4 5 7 10
4
4 5 7 11
4
4 5 7 12
4
4 5 7 13
4
4 5 7 14
4
4 5 7 15
4
4 5 7 16
1
3
5
1
4
3
0
0
0
1

For x={4,5,7,9}x=\{4,5,7,9\}, the five possible triples are as follows:

$$(2, 2, 5), (2, 3, 4), (2, 4, 5), (3, 4, 5), (4, 5, 7). $$

Scoring

  • In test cases 1-4, all xix_i are at most 5050.
  • Test cases 5-6 satisfy N=7N=7.
  • Test cases 7-15 satisfy no additional constraints.

Problem Credits

Benjamin Qi