Data Stream as Disjoint Intervals
给一个intervals的stream, 求写一个API. 这个要利用java treemap的内建方法.
public class SummaryRanges {
TreeMap<Integer, Interval> tree;
public SummaryRanges() {
tree = new TreeMap<>();
}
public void addNum(int val) {
if(tree.containsKey(val)) return;
Integer l = tree.lowerKey(val);
Integer h = tree.higherKey(val);
if(l != null && h != null && tree.get(l).end + 1 == val && h == val + 1) {
tree.get(l).end = tree.get(h).end;
tree.remove(h);
} else if(l != null && tree.get(l).end + 1 >= val) {
tree.get(l).end = Math.max(tree.get(l).end, val);
} else if(h != null && h == val + 1) {
tree.put(val, new Interval(val, tree.get(h).end));
tree.remove(h);
} else {
tree.put(val, new Interval(val, val));
}
}
public List<Interval> getIntervals() {
return new ArrayList<>(tree.values());
}
}