Unforgivable Curse (easy version)

题意翻译

与 E2 的差异仅在 $k$ 的取值不同。 给定两个长度为 $n$ 的字符串 $s_1,s_2$ 以及一个正整数 $k$，你可以进行任意次操作（可以不操作）： 若 $|i-j|=k$ 或 $|i-j|=k+1$，交换 $s_2$ 第 $i$ 个位置的字符与第 $j$ 个位置的字符。 问最终能否使得 $s_1,s_2$ 完全相同。 本题有多组测试数据。 $1\leq T\leq 10^4,1\leq n\leq 2\times 10^5,k=3,\sum n\leq 2\times 10^5$ translated by @[StayAlone](https://www.luogu.com.cn/user/409236)

题目描述

This is an easy version of the problem. In this version, $ k $ is always $ 3 $ . The chief wizard of the Wizengamot once caught the evil wizard Drahyrt, but the evil wizard has returned and wants revenge on the chief wizard. So he stole spell $ s $ from his student Harry. The spell — is a $ n $ -length string of lowercase Latin letters. Drahyrt wants to replace spell with an unforgivable curse — string $ t $ . Drahyrt, using ancient magic, can swap letters at a distance $ k $ or $ k+1 $ in spell as many times as he wants. In this version of the problem, you can swap letters at a distance of $ 3 $ or $ 4 $ . In other words, Drahyrt can change letters in positions $ i $ and $ j $ in spell $ s $ if $ |i-j|=3 $ or $ |i-j|=4 $ . For example, if $ s = $ "talant" and $ t = $ "atltna", Drahyrt can act as follows: - swap the letters at positions $ 1 $ and $ 4 $ to get spell "aaltnt". - swap the letters at positions $ 2 $ and $ 6 $ to get spell "atltna". You are given spells $ s $ and $ t $ . Can Drahyrt change spell $ s $ to $ t $ ?

输入输出格式

输入格式

The first line of input gives a single integer $ T $ ( $ 1 \le T \le 10^4 $ ) — the number of test cases in the test. Descriptions of the test cases are follow. The first line contains two integers $ n, k $ ( $ 1 \le n \le 2 \cdot 10^5 $ , $ k = 3 $ ) — the length spells and the number $ k $ such that Drahyrt can change letters in a spell at a distance $ k $ or $ k+1 $ . The second line gives spell $ s $ — a string of length $ n $ consisting of lowercase Latin letters. The third line gives spell $ t $ — a string of length $ n $ consisting of lowercase Latin letters. It is guaranteed that the sum of $ n $ values over all test cases does not exceed $ 2 \cdot 10^5 $ . Note that there is no limit on the sum of $ k $ values over all test cases.

输出格式

For each test case, output on a separate line "YES" if Drahyrt can change spell $ s $ to $ t $ and "NO" otherwise. You can output the answer in any case (for example, lines "yEs", "yes", "Yes" and "YES" will be recognized as positive answer).

输入输出样例

输入样例 #1

7
6 3
talant
atltna
7 3
abacaba
aaaabbc
12 3
abracadabraa
avadakedavra
5 3
accio
cicao
5 3
lumos
molus
4 3
uwjt
twju
4 3
kvpx
vxpk

输出样例 #1

YES
YES
NO
YES
NO
YES
NO

说明

The first example is explained in the condition. In the second example we can proceed as follows: - Swap the letters at positions $ 2 $ and $ 5 $ (distance $ 3 $ ), then we get the spell "aaacbba". - Swap the letters at positions $ 4 $ and $ 7 $ (distance $ 3 $ ), then you get the spell "aaaabbc". In the third example, we can show that it is impossible to get the string $ t $ from the string $ s $ by swapping the letters at a distance of $ 3 $ or $ 4 $ . In the fourth example, for example, the following sequence of transformations is appropriate: - "accio" $ \rightarrow $ "aocic" $ \rightarrow $ "cocia" $ \rightarrow $ "iocca" $ \rightarrow $ "aocci" $ \rightarrow $ "aicco" $ \rightarrow $ "cicao" In the fifth example, you can show that it is impossible to get the string $ s $ from the string $ t $ . In the sixth example, it is enough to swap the two outermost letters.