speed test php, python, ruby

n! means n * (n-1) * ... * 3 * 2 * 1
For example 10! = 10 * 9 * 8 *...* 3*2*1 = 3628800
Let R(n) equal the sum of the digits in the number n!
For example, R(10) = 3 + 6 + 2 + 8 + 8 + 0 + 0 = 27
Find the lowest value for n where R(n) is 8001

Configuration:
Debian squeeze 6.0.3
Kernel Linux 2.6.32
RAM: 4 GB
Processor: Pentium Dual-core E5700 @ 3 GHz

PHP 5.3.3-7+squeeze3
Python 2.6.6 (r266:84292, Dec 26 2010, 22:31:48)
ruby 1.8.7 (2010-08-16 patchlevel 302) [x86_64-linux]

[ArcWeltraumpert]

This is 2024, and ruby was improving their performance, and they now have other variant besides cruby, like jruby, truffleruby, mruby, even jit via yjit for cruby (mri).

[music-bkee]

Just tested (7 years later) ruby example with ruby 2.5, took 0.3 seconds and no crashing. And python 3.5 example took 0.4 seconds. My CPU is 4.5 GHz.

[zadahmed]

These languages are not meant to give you fast performance they are meant to give you fast shipping

[oisnot]

In PHP use gmp_fact and gmp_strval. Easy.