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This should be a simple one compared to the rest of the problems on this list. Think of the big string as a word, and each number as a letter. Then this is a simple word problem with repeated values. Since there are 20 total letters and repeated multiplicities of 2,4,3,1,2,3,2,3 respectively, therefore the answer is:

$ \frac{20!}{2!\times 4! \times 3! \times 1! \times 2! \times 3! \times 2! \times 3!} $

-mkburges


But, don't we have to subtract the cases that are starting with 0s? --Lee 17:51, 11 February 2009 (UTC)

ㄴI thought so because if it starts with 0, it would not be 20 decimal digits...right?? but seems like we do not need to consider that case as an exception..


we do not need to subtract them because they are strings and not numbers ---Kristen 18:33, 11 February 2009 (UTC)


This problem is the same as "MISSISSIPPI" which we did in the class..

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