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Evil Straw Warts Live

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A palindrome is a string of symbols that is equal to itself when reversed. Given an input string, not necessarily a palindrome, compute the number of swaps necessary to transform the string into a palindrome. By swap we mean reversing the order of two adjacent symbols. For example, the string “mamad” may be transformed into the palindrome “madam” with 3 swaps:

swap “ad” to yield “mamda”
swap “md” to yield “madma”
swap “ma” to yield “madam”

Input

The first line of input gives $1 \le n \le 200$, the number of test cases. For each test case, one line of input follows, containing a string of up to $100$ lowercase letters.

Output

Output consists of one line per test case. This line will contain the number of swaps, or “Impossible” if it is not possible to transform the input to a palindrome.

Sample Input 1	Sample Output 1
3 mamad asflkj aabb	3 Impossible 2

CPU Time limit 1 second

Memory limit 1024 MB

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Author

Gordon V. Cormack

Source Waterloo Programming Contest 2004-09-19

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