For given positive integer n, what is the last non-zero digit of n!?
Example: factorial(11) = 39916800
Last non-zero digit is 8.
Optional: Can you make an efficient algorithm for very large n?
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1 Comment
James
on 16 Feb 2017
Need a better test suite to prevent cheesy solutions like this one. :-) Some N>10 values in there would help. N>50 would be even better.
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