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/* lran2.h
* by Wolfram Gloger 1996.
*
* A small, portable pseudo-random number generator.
*/
#ifndef _LRAN2_H
#define _LRAN2_H
#define LRAN2_MAX 714025l /* constants for portable */
#define IA 1366l /* random number generator */
#define IC 150889l /* (see e.g. `Numerical Recipes') */
struct lran2_st {
long x, y, v[97];
};
static void
lran2_init(struct lran2_st* d, long seed)
{
long x;
int j;
x = (IC - seed) % LRAN2_MAX;
if(x < 0) x = -x;
for(j=0; j<97; j++) {
x = (IA*x + IC) % LRAN2_MAX;
d->v[j] = x;
}
d->x = (IA*x + IC) % LRAN2_MAX;
d->y = d->x;
}
#ifdef __GNUC__
__inline__
#endif
static long
lran2(struct lran2_st* d)
{
int j = (d->y % 97);
d->y = d->v[j];
d->x = (IA*d->x + IC) % LRAN2_MAX;
d->v[j] = d->x;
return d->y;
}
#undef IA
#undef IC
#endif
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