void appendIfAbsent(ActiveList al) {
if (_n + al._n > _a.length) growTo(2 * (_n + al._n));
int n = al._n;
for (int i = 0; i < n; ++i) {
Sample s = al.get(i);
if (s.absent) {
_a[_n++] = s;
s.absent = false;
}
}
}
private void clearActivated(Sample s) {
s.activated = 0;
}
private void setActivated(Sample s) {
s.activated = _activated;
}
void append(Sample s) {
s.activated = _activated;
if (_n == _a.length) growTo(2 * _n);
_a[_n++] = s;
}