题目描述
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 $A$, $B$, and $C$ ($1\le A\le B\le C$). These
integers are supposed to be secret, so she will not directly reveal them to her
sister Bessie. Instead, she tells Bessie $N$ ($4\le N\le 7$) distinct
integers $x_1,x_2,\ldots,x_N$ ($1\le x_i\le 10^9$), claiming that each $x_i$ is
one of $A$, $B$, $C$, $A+B$, $B+C$, $C+A$, or $A+B+C$. However, Elsie may be
lying; the integers $x_i$ might not correspond to any valid triple $(A,B,C)$.
This is too hard for Bessie to wrap her head around, so it is up to you to
determine the number of triples $(A,B,C)$ that are consistent with the numbers Elsie
presented (possibly zero).
Each input file will contain $T$ ($1\le T\le 100$) test cases that should be
solved independently.
INPUT FORMAT (input arrives from the terminal / stdin):
The first input line contains $T$.
Each test case starts with $N$, the number of integers Elsie gives to Bessie.
The second line of each test case contains $N$ distinct integers
$x_1,x_2,\ldots,x_N$.
OUTPUT FORMAT (print output to the terminal / stdout):
For each test case, output the number of triples $(A,B,C)$ that are consistent
with the numbers Elsie presented.
SAMPLE INPUT:
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
SAMPLE OUTPUT:
1
3
5
1
4
3
0
0
0
1
For $x=\{4,5,7,9\}$, 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 $x_i$ are at most $50$.Test cases 5-6 satisfy $N=7$.Test cases 7-15 satisfy no additional constraints.
Problem credits: Benjamin Qi
输入格式
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输出格式
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