题意
给出
n
<script type="math/tex" id="MathJax-Element-6">n</script>个区间,合并连续的区间并进行分块
思路
使用贪心的思想,按照起始点和结束点进行排序,然后遍历记录当前块的起始点和结束点,如果遍历点不在当前块内,存储当前块,然后重新分块,更新当前块.
代码
class Solution {
public:
vector<Interval> merge(
vector<Interval>& intervals) {
vector<Interval>ans;
size_t len = intervals.size();
if(len ==
0)
return ans;
sort(intervals.begin(), intervals.end(), cmp);
int L = intervals[
0].start, R = intervals[
0].end;
for(
int i =
1; i < len; i++){
if(intervals[i].start <= R){
R = max(R, intervals[i].end);
}
else{
ans.push_back(Interval(L, R));
L = intervals[i].start;
R = intervals[i].end;
}
}
ans.push_back(Interval(L, R));
return ans;
}
private:
static bool cmp(Interval A, Interval B){
if(A.start == B.start){
return A.end < B.end;
}
return A.start < B.start;
}
};