long  [] tmpl = _ls; _ls = nc._ls; nc._ls = tmpl;
int   [] tmpi = _xs; _xs = nc._xs; nc._xs = tmpi;
tmpi = _id; _id = nc._id; nc._id = tmpi;
double[] tmpd = _ds; _ds = nc._ds; nc._ds = tmpd;
int      tmp  = _len; _len=nc._len; nc._len=tmp;
<BUG>_len2=_len;
add(nc);</BUG>
}
<BUG>void append2( long l, int x ) {
if(_id == null || l != 0){</BUG>
if(_ls == null || _len == _ls.length) {

long  [] tmpl = _ls; _ls = nc._ls; nc._ls = tmpl;
int   [] tmpi = _xs; _xs = nc._xs; nc._xs = tmpi;
tmpi = _id; _id = nc._id; nc._id = tmpi;
double[] tmpd = _ds; _ds = nc._ds; nc._ds = tmpd;
int      tmp  = _len; _len=nc._len; nc._len=tmp;
tmp  = _len2; _len2 = nc._len2; nc._len2 = tmp;
add(nc);
}
void append2( long l, int x ) {
assert _ds == null;
if(_id == null || l != 0){
if(_ls == null || _len == _ls.length) {
