24 lines
327 B
C
24 lines
327 B
C
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#include <u.h>
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#include <libc.h>
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#include <libsec.h>
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#define Maxrand ((1UL<<31)-1)
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ulong
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nfastrand(ulong n)
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{
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ulong m, r;
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/*
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* set m to the maximum multiple of n <= 2^31-1
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* so we want a random number < m.
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*/
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if(n > Maxrand)
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abort();
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m = Maxrand - Maxrand % n;
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while((r = fastrand()) >= m)
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;
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return r%n;
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}
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