You are given a permutation $a_1, a_2, \ldots, a_n$ of size $n$, where each integer from $1$ to $n$ appears exactly once.
You can do the following operation any number of times (possibly, zero):
- Choose any three indices
$i, j, k$($1 \le i \lt j \lt k \le n$). - If
$a_i \gt a_k$, replace$a_i$with$a_i + a_j$. Otherwise, swap$a_j$and$a_k$.
Determine whether you can make the array $a$ sorted in non-descending order.
Input
Each test consists of multiple test cases. The first line contains a single integer $t$ ($1 \le t \le 5000$) — the number of test cases. The description of test cases follows.
The first line of each test case contains a single integer $n$ ($3 \le n \le 10$) — the length of the array $a$.
The second line contains $n$ integers $a_1,a_2,\dots,a_n$ ($1 \le a_i \le n$, $a_i \neq a_j$ if $i \neq j$) — the elements of the array $a$.
Output
For each test case, output "Yes" (without quotes) if the array can be sorted in non-descending order, and "No" (without quotes) otherwise.
You can output "Yes" and "No" in any case (for example, strings "YES", "yEs" and "yes" will be recognized as a positive response).
Note
In the first test case, $[1,2,3]$ is already sorted in non-descending order.
In the second test case, we can choose $i = 1,j = 2,k = 3$. Since $a_1 \le a_3$, swap $a_2$ and $a_3$, the array then becomes $[1,2,3]$, which is sorted in non-descending order.
In the seventh test case, we can do the following operations successively:
- Choose
$i = 5,j = 6,k = 7$. Since$a_5 \le a_7$, swap$a_6$and$a_7$, the array then becomes$[1,2,6,7,4,5,3]$. - Choose
$i = 5,j = 6,k = 7$. Since$a_5 \gt a_7$, replace$a_5$with$a_5+a_6=9$, the array then becomes$[1,2,6,7,9,5,3]$. - Choose
$i = 2,j = 5,k = 7$. Since$a_2 \le a_7$, swap$a_5$and$a_7$, the array then becomes$[1,2,6,7,3,5,9]$. - Choose
$i = 2,j = 4,k = 6$. Since$a_2 \le a_6$, swap$a_4$and$a_6$, the array then becomes$[1,2,6,5,3,7,9]$. - Choose
$i = 1,j = 3,k = 5$. Since$a_1 \le a_5$, swap$a_3$and$a_5$, the array then becomes$[1,2,3,5,6,7,9]$, which is sorted in non-descending order.
In the third, the fourth, the fifth and the sixth test cases, it can be shown that the array cannot be sorted in non-descending order.
样例
7
3
1 2 3
3
1 3 2
7
5 3 4 7 6 2 1
7
7 6 5 4 3 2 1
5
2 1 4 5 3
5
2 1 3 4 5
7
1 2 6 7 4 3 5
Yes
Yes
No
No
No
No
Yes
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