Method merge

src/com/blankj/medium/_0056/Solution.java:18–42

(List<Interval> intervals)

 */
public class Solution {
    public List<Interval> merge(List<Interval> intervals) {
        if (intervals == null || intervals.size() <= 1) return intervals;
        intervals.sort(new Comparator<Interval>() {
            @Override
            public int compare(Interval o1, Interval o2) {
                if (o1.start < o2.start) return -1;
                if (o1.start > o2.start) return 1;
                return 0;
            }
        });
        List<Interval> ans = new ArrayList<>();
        int start = intervals.get(0).start;
        int end = intervals.get(0).end;
        for (Interval interval : intervals) {
            if (interval.start <= end) {
                end = Math.max(end, interval.end);
            } else {
                ans.add(new Interval(start, end));
                start = interval.start;
                end = interval.end;
            }
        }
        ans.add(new Interval(start, end));
        return ans;
    }

    public static void main(String[] args) {
        Solution solution = new Solution();