Problem 44067. The last non-zero digit of a factorial

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?

Solution Stats

70.0% Correct | 30.0% Incorrect
Last Solution submitted on Jan 02, 2020

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