[leetcode]Insert Interval

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].

这道题是个好题。我的算法太渣了,直接贴人家的吧。

思路1 : 二分查找插入区间,具体代码我没实现,大家直接戳这里->传送门

 

 

思路2 : 传送门

一般来说,只有这三种情况,交叉有着四种情况,其实大家还是看代码吧,代码比图还好看。。。

 1 public class Solution {
 2     public List<Interval> insert(List<Interval> intervals, Interval newInterval) {
 3         List<Interval> res = new ArrayList<Interval>();
 4         for (Interval each : intervals) {
 5             if (each.end < newInterval.start)
 6                 res.add(each);
 7             else if (each.start > newInterval.end) {
 8                 res.add(newInterval);
 9                 newInterval = each;
10             } else {
11                 newInterval = new Interval(Math.min(each.start, newInterval.start), Math.max(each.end, newInterval.end));
12             }
13         }
14         res.add(newInterval);
15         return res;
16     }
17 }

 

posted on 2014-07-25 22:16  喵星人与汪星人  阅读(172)  评论(0编辑  收藏  举报