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CF1673B.A Perfectly Balanced String?
A Perfectly Balanced String?
Let's call a string perfectly balanced if for all possible triplets such that is a non-empty substring of and and are characters present in , the difference between the frequencies of and in is not more than .
For example, the strings "aba" and "abc" are perfectly balanced but "abb" is not because for the triplet ("bb",'a','b'), the condition is not satisfied.
You are given a string consisting of lowercase English letters only. Your task is to determine whether is perfectly balanced or not.
A string is called a substring of another string if can be obtained by deleting some characters (possibly ) from the start and some characters (possibly ) from the end of .
Input
The first line of input contains a single integer () denoting the number of testcases.
Each of the next lines contain a single string (), consisting of lowercase English letters.
It is guaranteed that the sum of over all testcases does not exceed .
Output
For each test case, print "YES" if is a perfectly balanced string, and "NO" otherwise.
You may print each letter in any case (for example, "YES", "Yes", "yes", "yEs" will all be recognized as positive answer).
Note
Let represent the frequency of character in string .
For the first testcase we have
It can be seen that for any substring of , the difference between and is not more than . Hence the string is perfectly balanced.
For the second testcase we have
It can be seen that for the substring , the difference between and is which is greater than . Hence the string is not perfectly balanced.
For the third testcase we have
It can be seen that for any substring of and any two characters , the difference between and is not more than . Hence the string is perfectly balanced.
Samples
5
aba
abb
abc
aaaaa
abcba
YES
NO
YES
YES
NO
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