Cody

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

Created by Jihye Sofia Seo

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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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Solution Stats

30 Solutions
15 Solvers

Last Solution submitted on Jan 02, 2020

Last 200 Solutions

Problem Comments

Solution Comments

Solution 1124528

1 Comment

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.

Problem Recent Solvers15

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Problem Tags

factorial

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