Merge intervals

mergeintervals.java

public static ArrayList<Interval> insertRange(ArrayList<Interval> intervalsList, Interval insert) {
    ArrayList<Interval> out = new ArrayList<>();
    for(Interval i: intervalsList){
        if(i.end < insert.start) {
            out.add(i);
        }
        else if(i.start > insert.end) {
            out.add(insert);
            insert = i;
        }
        else if(i.start <= insert.end || i.end >= insert.start){
            int newStart = Math.min(i.start, insert.start);
            int newEnd = Math.max(i.end, insert.end);
            insert = new Interval(newStart, newEnd);
        }
    }
    out.add(insert);
    return out;
}