text: public SmallDocSet union(SmallDocSet other) {SmallDocSet bigger;SmallDocSet smaller;if (other.intSet.size() > this.intSet.size()) {bigger = other;smaller = this;} else {bigger = this;smaller = other;}for (int v : smaller.intSet.keys) {if (v == smaller.intSet.emptyVal)continue;bigger.set(v);}return bigger;}