Reversed Differences 

  abc
- cba
-----
 (a,b,c in some order)
In the above difference equation, a, b, and c are three distinct digits. When the three digit number cba is subtracted from the three digit number abc, another three digit number results, composed of the digits a, b, and c in some order. Find the corresponding digits.

Repeat the problem for N digits (4<=N<=10). That is, subtract an N-digit number from its reverse to result in another N-digit number, such that each of the three consist of the same N distinct digits. Try to find the answer with the largest difference.

Source: Original extension of a problem from The Little Giant Encyclopedia of Puzzles.

Solution
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