57. Insert Interval

Given a set of non-overlapping intervals, insert a new interval into the intervals (merge if necessary).

You may assume that the intervals were initially sorted according to their start times.

Example 1:
Given intervals [1,3],[6,9], insert and merge [2,5] in as [1,5],[6,9].
Example 2:
Given [1,2],[3,5],[6,7],[8,10],[12,16], insert and merge [4,9] in as [1,2],[3,10],[12,16].

This is because the new interval [4,9] overlaps with [3,5],[6,7],[8,10].

Analysis

link: https://leetcode.com/problems/insert-interval/discuss/21600/Short-java-code

Solution from Forum

public List<Interval> insert(List<Interval> intervals, Interval newInterval) {
    List<Interval> result = new ArrayList<Interval>();
    for (Interval i : intervals) {
        if (newInterval == null || i.end < newInterval.start)
            result.add(i);
        else if (i.start > newInterval.end) {
            result.add(newInterval);
            result.add(i);
            newInterval = null;
        } else {
            newInterval.start = Math.min(newInterval.start, i.start);
            newInterval.end = Math.max(newInterval.end, i.end);
        }
    }
    if (newInterval != null) {
        result.add(newInterval);
    }
    return result;
}