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CF2121B.Above the Clouds
Above the Clouds
You are given a string of length , consisting of lowercase letters of the Latin alphabet. Determine whether there exist three non-empty strings , , and such that:
- , meaning the concatenation of strings , , and equals .
- The string is a substring of the string , which is the concatenation of strings and .
Concatenation of strings and is defined as the string , where and are the lengths of strings and , respectively. For example, the concatenation of the strings "code" and "forces" is "codeforces".
A string is a substring of a string if can be obtained from by the deletion of several (possibly, zero or all) characters from the beginning and several (possibly, zero or all) characters from the end.
Input
Each test consists of multiple test cases. The first line contains a single integer () — the number of test cases. The description of the test cases follows.
The first line of each test case contains a single integer () — the length of the string .
The second line of each test case contains the string of length , consisting of lowercase letters of the Latin alphabet.
It is guaranteed that the sum of across all test cases does not exceed .
Output
For each test case, output "Yes" if there exist three non-empty strings , , and that satisfy the conditions, and "No" otherwise.
You may output the answer in any case (upper or lower). For example, the strings "yEs", "yes", "Yes", and "YES" will be recognized as positive answers.
Note
In the first test case, there exist unique non-empty strings , , and such that . These are the strings "a", "a", and "a". The concatenation of strings and equals "aa". The string is a substring of this string.
In the sixth test case, one can choose "a", "ab", and "b". The concatenation of strings and equals "ab". The string is a substring of this string.
In the seventh test case, one can choose "ab", "a", and "ca". The concatenation of strings and equals "abca". The string is a substring of this string.
Samples
12
3
aaa
3
aba
3
aab
4
abca
4
abba
4
aabb
5
abaca
5
abcda
5
abcba
6
abcbbf
6
abcdaa
3
abb
Yes
No
Yes
No
Yes
Yes
Yes
No
Yes
Yes
Yes
Yes
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