Shirlies
宁静专注认真的程序媛~

题目:

228. Summary Ranges

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"].

答案:

就是找连续的序列。

直接判断相邻数据大小是否相差为1即可,主要是注意最后的数字要特殊考虑一下。

链接:

https://leetcode.com/problems/summary-ranges/

代码:

 1 #include <vector>
 2 #include <string>
 3 #include <sstream>
 4 
 5 using std::vector;
 6 using std::string;
 7 using std::ostringstream;
 8 
 9 class Solution {
10 private:
11     string num2str(int& num)
12     {
13         ostringstream stream;
14         stream << num;
15         return stream.str();
16     }
17     
18 public:
19     vector<string> summaryRanges(vector<int>& nums) {
20         unsigned int len = nums.size();
21         unsigned int index,inIndex;
22         unsigned int minIndex = 0;
23         unsigned int maxIndex = 0;
24         
25         vector<string> ans;
26         if(len == 0)
27         {
28             return ans;
29         }
30         
31         if(len == 1)
32         {
33             ans.push_back(num2str(nums[0]));
34             return ans;
35         }
36         
37         for(index = 0; index < len - 1; ++ index)
38         {
39             if(nums[index] + 1 == nums[index + 1])
40             {
41                 maxIndex = index + 1;
42             }else
43             {
44                 string tmp = "";
45                 tmp += num2str(nums[minIndex]);
46                 if(maxIndex > minIndex)
47                 {
48                     tmp += "->";
49                     tmp += num2str(nums[maxIndex]);
50                 }
51                 ans.push_back(tmp);
52                 
53                 minIndex = index + 1;
54                 maxIndex = index + 1;
55             }
56         }
57         
58         if(nums[len-2] + 1 == nums[len - 1])
59         {
60             maxIndex = len - 1;
61         }else
62         {
63             minIndex = len - 1;
64             maxIndex = len - 1;
65         }
66         
67         string tmp = "";
68         tmp += num2str(nums[minIndex]);
69         if(maxIndex > minIndex)
70         {
71             tmp += "->";
72             tmp += num2str(nums[maxIndex]);
73         }
74         ans.push_back(tmp);
75                 
76         return ans;
77     }
78 };
View Code

 

posted on 2016-07-16 15:20  Shirlies  阅读(306)  评论(0编辑  收藏  举报