MLton code Copyright 2013 Ivan Raikov.

randmtziglib.c Coded by Takuji Nishimura and Makoto Matsumoto.
This is a faster version by taking Shawn Cokus's optimization,
Matthe Bellew's simplification, Isaku Wada's real version.
David Bateman added normal and exponential distributions following
Marsaglia and Tang's Ziggurat algorithm.

Copyright (C) 1997 - 2002, Makoto Matsumoto and Takuji Nishimura,
Copyright (C) 2004, David Bateman

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