[leetcode]Insert Interval @ Python

原题地址：https://oj.leetcode.com/problems/insert-interval/

题意：

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：最简单的方法是将要插入的区间和原来的区间合在一起排序，然后按照merge intervals的方法来编程。

代码：

# Definition for an interval.
# class Interval:
#     def __init__(self, s=0, e=0):
#         self.start = s
#         self.end = e

class Solution:
    # @param intervals, a list of Intervals
    # @param newInterval, a Interval
    # @return a list of Interval
    # @should rewrite without sort!!!
    def insert(self, intervals, newInterval):
        intervals.append(newInterval)
        intervals.sort(key = lambda x:x.start)
        length=len(intervals)
        res=[]
        for i in range(length):
            if res==[]:
                res.append(intervals[i])
            else:
                size=len(res)
                if res[size-1].start<=intervals[i].start<=res[size-1].end:
                    res[size-1].end=max(intervals[i].end, res[size-1].end)
                else:
                    res.append(intervals[i])
        return res