/* the alarm condition table */
int table[]={ 0, 0, 1, 0, 1, 1, 1, 1, 1};

int sum; /* the variable used to accumulate neighbor density */
nbr y; /* the variable used in the scanning of neighbors */

/* The default is no change to all fields */
default value=value;
default alarm=alarm;
default counter=counter;

/* scanning neighbors */
sum=0;
over each other y: /* loop through all neighbors */
  if (y:value) sum++;  /* if a neighbor is active, increase sum */

/* alarm bit is set according to the density collected */
alarm=table[sum];

/* value is cleared if counter is running, otherwise it is enabled */
if (counter==0)
  value=1;
else
  value=0;

/* if alarm is set and the cell is active, counter starts */
if (value && alarm)
  counter=3;
else if (counter) /* counter always counts down to zero */
  counter--;