/* Copyright Will Wilson 1999 */
/* birth-death simulation */

#include	<stdlib.h>
#include	<stdio.h>

#define	MAXTIME 	100
#define	PRNTTIME	10

int main(void)
{
	int	ttt, event, n;
	int	seed;
	double	alpha, beta;

	alpha = beta = 0.1;
	n = 10;

	seed = 1456739853;

	srand48(seed);
	printf(" time   pop\n");

	for(ttt=0;ttt<MAXTIME;ttt++)
	{
		event = 0;
		if(drand48()<alpha) event = 1;
		if(drand48()<beta) event = event - 1;
		n += event;
		if(n<0) n = 0;

		if(ttt%PRNTTIME==0)
			printf(" %3d   %-4d\n",ttt, n);
	}
	return (0);
}