CF1256F.Equalizing Two Strings

You are given two strings $s$ and $t$ both of length $n$ and both consisting of lowercase Latin letters.

In one move, you can choose any length $len$ from $1$ to $n$ and perform the following operation:

• Choose any contiguous substring of the string $s$ of length $len$ and reverse it;
• at the same time choose any contiguous substring of the string $t$ of length $len$ and reverse it as well.

Note that during one move you reverse exactly one substring of the string $s$ and exactly one substring of the string $t$ .

Also note that borders of substrings you reverse in $s$ and in $t$ can be different, the only restriction is that you reverse the substrings of equal length. For example, if $len=3$ and $n=5$ , you can reverse $s[1 \dots 3]$ and $t[3 \dots 5]$ , $s[2 \dots 4]$ and $t[2 \dots 4]$ , but not $s[1 \dots 3]$ and $t[1 \dots 2]$ .

Your task is to say if it is possible to make strings $s$ and $t$ equal after some (possibly, empty) sequence of moves.

You have to answer $q$ independent test cases.

The first line of the input contains one integer $q$ ( $1 \le q \le 10^4$ ) — the number of test cases. Then $q$ test cases follow.

The first line of the test case contains one integer $n$ ( $1 \le n \le 2 \cdot 10^5$ ) — the length of $s$ and $t$ .

The second line of the test case contains one string $s$ consisting of $n$ lowercase Latin letters.

The third line of the test case contains one string $t$ consisting of $n$ lowercase Latin letters.

It is guaranteed that the sum of $n$ over all test cases does not exceed $2 \cdot 10^5$ ( $\sum n \le 2 \cdot 10^5$ ).

For each test case, print the answer on it — "YES" (without quotes) if it is possible to make strings $s$ and $t$ equal after some (possibly, empty) sequence of moves and "NO" otherwise.