CF1375C.Element Extermination

You are given an array $a$ of length $n$, which initially is a permutation of numbers from $1$ to $n$. In one operation, you can choose an index $i$ ($1 \leq i \lt n$) such that $a_i \lt a_{i + 1}$, and remove either $a_i$ or $a_{i + 1}$ from the array (after the removal, the remaining parts are concatenated).

For example, if you have the array $[1, 3, 2]$, you can choose $i = 1$ (since $a_1 = 1 \lt a_2 = 3$), then either remove $a_1$ which gives the new array $[3, 2]$, or remove $a_2$ which gives the new array $[1, 2]$.

Is it possible to make the length of this array equal to $1$ with these operations?

给你一个长度为 $n$ 的数组 $a$，该数组初始时是 $1$ 到 $n$ 的一个排列。在一次操作中，你可以选择一个下标 $i$（满足 $1 \leq i \lt n$），使得 $a_i \lt a_{i + 1}$，然后从数组中删除 $a_i$ 或 $a_{i + 1}$ 中的任意一个（删除后，剩余部分会直接拼接）。

例如，若当前数组为 $[1, 3, 2]$，你可以选择 $i = 1$（因为 $a_1 = 1 \lt a_2 = 3$），然后删除 $a_1$，得到新数组 $[3, 2]$；或者删除 $a_2$，得到新数组 $[1, 2]$。

能否通过若干次上述操作，使该数组的长度变为 $1$？

The first line contains a single integer $t$ ($1 \leq t \leq 2 \cdot 10^4$) — the number of test cases. The description of the test cases follows.

The first line of each test case contains a single integer $n$ ($2 \leq n \leq 3 \cdot 10^5$) — the length of the array.

The second line of each test case contains $n$ integers $a_1$, $a_2$, ..., $a_n$ ($1 \leq a_i \leq n$, $a_i$ are pairwise distinct) — elements of the array.

It is guaranteed that the sum of $n$ over all test cases doesn't exceed $3 \cdot 10^5$.

第一行包含一个整数 $t$（$1 \leq t \leq 2 \cdot 10^4$）——测试用例的数量。随后是各测试用例的描述。

每个测试用例的第一行包含一个整数 $n$（$2 \leq n \leq 3 \cdot 10^5$）——数组的长度。

每个测试用例的第二行包含 $n$ 个整数 $a_1$, $a_2$, ..., $a_n$（$1 \leq a_i \leq n$，且 $a_i$ 两两互不相同）——数组的元素。

保证所有测试用例的 $n$ 之和不超过 $3 \cdot 10^5$。

For each test case, output on a single line the word "YES" if it is possible to reduce the array to a single element using the aforementioned operation, or "NO" if it is impossible to do so.

对于每个测试用例，如果可以通过上述操作将数组缩减为单个元素，则在一行中输出单词 “YES”；否则（即无法做到），输出 “NO”。

For the first two test cases and the fourth test case, we can operate as follow (the bolded elements are the pair chosen for that operation):

$[\text{1}, \textbf{2}, \textbf{3}] \rightarrow [\textbf{1}, \textbf{2}] \rightarrow [\text{1}]$

$[\text{3}, \textbf{1}, \textbf{2}, \text{4}] \rightarrow [\text{3}, \textbf{1}, \textbf{4}] \rightarrow [\textbf{3}, \textbf{4}] \rightarrow [\text{4}]$

$[\textbf{2}, \textbf{4}, \text{6}, \text{1}, \text{3}, \text{5}] \rightarrow [\textbf{4}, \textbf{6}, \text{1}, \text{3}, \text{5}] \rightarrow [\text{4}, \text{1}, \textbf{3}, \textbf{5}] \rightarrow [\text{4}, \textbf{1}, \textbf{5}] \rightarrow [\textbf{4}, \textbf{5}] \rightarrow [\text{4}]$

对于前两个测试用例和第四个测试用例，我们可以按如下方式操作（加粗的元素表示该次操作所选的数对）：

$[\text{1}, \textbf{2}, \textbf{3}] \rightarrow [\textbf{1}, \textbf{2}] \rightarrow [\text{1}]$

$[\text{3}, \textbf{1}, \textbf{2}, \text{4}] \rightarrow [\text{3}, \textbf{1}, \textbf{4}] \rightarrow [\textbf{3}, \textbf{4}] \rightarrow [\text{4}]$

$[\textbf{2}, \textbf{4}, \text{6}, \text{1}, \text{3}, \text{5}] \rightarrow [\textbf{4}, \textbf{6}, \text{1}, \text{3}, \text{5}] \rightarrow [\text{4}, \text{1}, \textbf{3}, \textbf{5}] \rightarrow [\text{4}, \textbf{1}, \textbf{5}] \rightarrow [\textbf{4}, \textbf{5}] \rightarrow [\text{4}]$