LeetCode#228 Summary Ranges

Problem Definition:

　　Given a sorted integer array without duplicates, return the summary of its ranges.

　　For example, given [0,1,2,4,5,7], return ["0->2","4->5","7"].

My Solution:

　　

 1 class Solution:
 2     # @param {integer[]} nums
 3     # @return {string[]}
 4     def summaryRanges(self, nums):
 5         sr=[]
 6         n=len(nums)
 7         if n==0:
 8             return sr
 9         start,end=0,0
10         p=1
11         while p<n:
12             if (nums[p]-nums[p-1])>1:
13                 end=p-1
14                 if start==end:
15                     sr.append(str(nums[start]))
16                 else:
17                     sr.append(str(nums[start])+"->"+str(nums[end]))
18                 start=p
19             p+=1
20         end=p-1
21         if start==end:
22             sr.append(str(nums[start]))
23         else:
24             sr.append(str(nums[start])+"->"+str(nums[end]))
25         return sr

 

 

而后在讨论区发现一个短小精悍的写法，显然我对Python太不熟练啦：

1 def summaryRanges(self, nums):
2   ranges, r = [], []
3   for n in nums:
4     if n-1 not in r:
5       r = []
6       ranges += r,
7     r[1:] = n,
8   return ['->'.join(map(str, r)) for r in ranges]

crux：

python的赋值和引用

 

posted @ 2015-07-16 11:45  曾可爱  阅读(159)  评论(0)  编辑  收藏  举报