LeetCode---Merge Intervals

题目链接

区间合并，贪心，需要注意边界情况，LeetCode的数据还是比较好的，这样才能写出健壮的程序。

 

附上代码：

 1 /**  2  * Definition for an interval.  3  * struct Interval {  4  * int start;  5  * int end;  6  * Interval() : start(0), end(0) {}  7  * Interval(int s, int e) : start(s), end(e) {}  8  * };  9  */

10 class Solution { 11 public: 12     vector<Interval> merge(vector<Interval> &intervals) { 13         typedef pair<int, int> pii; 14         vector<pii> my_pair; 15         for (unsigned int i = 0; i < intervals.size(); i++) { 16  my_pair.push_back(pii(intervals[i].start, intervals[i].end)); 17  } 18  sort(my_pair.begin(), my_pair.end()); 19         vector<Interval> ans; 20         //输入为空

21         if (intervals.size() == 0) { 22             return ans; 23  } 24         int beg = my_pair[0].first, ed = my_pair[0].second; 25         for (unsigned int i = 1; i < my_pair.size(); i++) { 26             if (my_pair[i].first <= ed) { 27                 ed = max(my_pair[i].second, ed); 28             } else { 29  ans.push_back(Interval(beg, ed)); 30                 beg = my_pair[i].first; 31                 ed = my_pair[i].second; 32  } 33  } 34         //处理最后一个数据

35         if (ans.size() == 0 || beg > ans[ans.size()-1].start) { 36  ans.push_back(Interval(beg, ed)); 37  } 38         

39         return ans; 40  } 41 };