public List<Interval> merge(List<Interval> intervals) {
		List<Interval> A=intervals;
		Collections.sort(A, (a,b)->	a.start-b.start);
		List<Interval> rel=new ArrayList<>();
		for (Interval i:A) {
			if (rel.isEmpty()) {
				rel.add(i);
			} else {
				Interval last=rel.get(rel.size()-1);
				if (last.end<i.start) {
					rel.add(i);
				} else {
					last.end=Math.max(last.end, i.end);
				}
			}
		}
		return rel;
	}