CF2167B.Your Name

khba is writing his girlfriend's name. He has $n$ cubes, each with one lowercase Latin letter written on it. They are arranged in a row, forming a string $s$. His girlfriend's name is also a string $t$, consisting of $n$ lowercase Latin letters.

To prove his love, he must check whether it is possible to rearrange the letters of string $s$ so that it becomes her name $t$.

khba 正在书写他女友的名字。他有 $n$ 个立方体，每个立方体上写有一个小写拉丁字母。这些立方体排成一行，构成字符串 $s$。他女友的名字也是一个由 $n$ 个小写拉丁字母组成的字符串 $t$。

为了证明他的爱意，他必须检查：能否重新排列字符串 $s$ 中的字母，使其恰好变成他女友的名字 $t$。

The first line contains an integer $q$ ($1 \le q \le 1000$) — the number of test cases.

The first line of each test case contains an integer $n$ ($1 \le n \le 20$).

The second line of each test case contains two distinct strings $s$ and $t$, each consisting of $n$ lowercase Latin letters.

第一行包含一个整数 $q$（$1 \le q \le 1000$）—— 表示测试用例的数量。

每个测试用例的第一行包含一个整数 $n$（$1 \le n \le 20$）。

每个测试用例的第二行包含两个互不相同的字符串 $s$ 和 $t$，每个字符串均由 $n$ 个小写拉丁字母组成。

For each test case, output "YES" if the letters of $s$ can be arranged to form $t$; otherwise, output "NO".

You can output the answer in any case (upper or lower). For example, the strings "yEs", "yes", "Yes" and "YES" will be recognized as positive responses.

对于每个测试用例，如果字符串 $s$ 的字母可以重新排列形成 $t$，则输出 "YES"；否则输出 "NO"。

你可以以任意大小写形式输出答案（大写或小写均可）。例如，字符串 "yEs"、"yes"、"Yes" 和 "YES" 均会被识别为肯定回答。

In the first example, the initial string is "humitsa", and the following operations can be performed:

• swap the first and third characters, resulting in "muhitsa"
• swap the second and fourth characters, resulting in "mihutsa"
• swap the third and fifth characters, resulting in "mithusa"
• swap the fourth and sixth characters, resulting in "mitsuha"

In the second example, the initial string is "orhi", and the following operations can be performed:

• swap the second and third characters, resulting in "ohri"
• swap the first and second characters, resulting in "hori"

在第一个例子中，初始字符串为 "humitsa"，可以执行以下操作：

• 交换第一个和第三个字符，得到 "muhitsa"
• 交换第二个和第四个字符，得到 "mihutsa"
• 交换第三个和第五个字符，得到 "mithusa"
• 交换第四个和第六个字符，得到 "mitsuha"

在第二个例子中，初始字符串为 "orhi"，可以执行以下操作：

• 交换第二个和第三个字符，得到 "ohri"
• 交换第一个和第二个字符，得到 "hori"