[LeetCode]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]. 

解题思路： insertion sort 的演变

Java Code:

public List insert(List intervals, Interval newInterval) {
           List res = new ArrayList(intervals);
        
        int s = 0;
        
        // at index s, the start is correct. we need to merge the end.
        while(s < intervals.size() && newInterval.start >= intervals.get(s).start){
            s++;
        }
        
        if(s > 0 && newInterval.start <= intervals.get(s-1).end){
            s--;
        }else{
            res.add(s, newInterval);
        }
        
        res.get(s).end = Math.max(newInterval.end, res.get(s).end);
        s++;
              
       while( s < res.size() && newInterval.end >= res.get(s).start){
           newInterval.end = Math.max(newInterval.end, res.get(s).end);
           res.remove(s);
       }
        
        return res;
    }