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CF1547B.Alphabetical Strings
Alphabetical Strings
A string of length () is called alphabetical if it can be obtained using the following algorithm:
- first, write an empty string to (i.e. perform the assignment
:= ""); - then perform the next step times;
- at the -th step take -th lowercase letter of the Latin alphabet and write it either to the left of the string or to the right of the string (i.e. perform the assignment
:=or:=, where is the -th letter of the Latin alphabet).
In other words, iterate over the first letters of the Latin alphabet starting from 'a' and etc. Each time we prepend a letter to the left of the string or append a letter to the right of the string . Strings that can be obtained in that way are alphabetical.
For example, the following strings are alphabetical: "a", "ba", "ab", "bac" and "ihfcbadeg". The following strings are not alphabetical: "z", "aa", "ca", "acb", "xyz" and "ddcba".
From the given string, determine if it is alphabetical.
Input
The first line contains one integer () — the number of test cases. Then test cases follow.
Each test case is written on a separate line that contains one string . String consists of lowercase letters of the Latin alphabet and has a length between and , inclusive.
Output
Output lines, each of them must contain the answer to the corresponding test case. Output YES if the given string is alphabetical and NO otherwise.
You can output YES and NO in any case (for example, strings yEs, yes, Yes and YES will be recognized as a positive answer).
Note
The example contains test cases from the main part of the condition.
Samples
11
a
ba
ab
bac
ihfcbadeg
z
aa
ca
acb
xyz
ddcba
YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
NO
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